diff --git a/icu4c/source/common/rbbiscan.cpp b/icu4c/source/common/rbbiscan.cpp
index f66a019f873..2d5c5ec1f02 100644
--- a/icu4c/source/common/rbbiscan.cpp
+++ b/icu4c/source/common/rbbiscan.cpp
@@ -192,13 +192,13 @@ RBBIRuleScanner::~RBBIRuleScanner() {
 //                              definitions problems.  I'm sure that there's a better way.
 //
 //----------------------------------------------------------------------------------------
-UBool RBBIRuleScanner::doParseActions(EParseAction action)
+UBool RBBIRuleScanner::doParseActions(int32_t action)
 {
     RBBINode *n       = NULL;
 
     UBool   returnVal = TRUE;
 
-    switch ((RBBI_RuleParseAction)action) {
+    switch (action) {
 
     case doExprStart:
         pushNewNode(RBBINode::opStart);
@@ -994,7 +994,7 @@ void RBBIRuleScanner::parse() {
         // We've found the row of the state table that matches the current input
         //   character from the rules string.
         // Perform any action specified  by this row in the state table.
-        if (doParseActions((EParseAction)tableEl->fAction) == FALSE) {
+        if (doParseActions((int32_t)tableEl->fAction) == FALSE) {
             // Break out of the state machine loop if the
             //   the action signalled some kind of error, or
             //   the action was to exit, occurs on normal end-of-rules-input.
diff --git a/icu4c/source/common/rbbiscan.h b/icu4c/source/common/rbbiscan.h
index 89748318eee..cd0bf94a4fb 100644
--- a/icu4c/source/common/rbbiscan.h
+++ b/icu4c/source/common/rbbiscan.h
@@ -1,7 +1,7 @@
 //
 //  rbbiscan.h
 //
-//  Copyright (C) 2002-2005, International Business Machines Corporation and others.
+//  Copyright (C) 2002-2007, International Business Machines Corporation and others.
 //  All Rights Reserved.
 //
 //  This file contains declarations for class RBBIRuleScanner
@@ -46,10 +46,6 @@ static const int    kStackSize = 100;               // The size of the state sta
                                                     //   to the depth of parentheses nesting
                                                     //   that is allowed in the rules.
 
-enum EParseAction {dummy01, dummy02};               // Placeholder enum for the specifier for
-                                                    //   actions that are specified in the
-                                                    //   rule parsing state table.
-
 class RBBIRuleScanner : public UMemory {
 public:
 
@@ -81,7 +77,7 @@ public:
     static UnicodeString stripRules(const UnicodeString &rules);
 private:
 
-    UBool       doParseActions(EParseAction a);
+    UBool       doParseActions(int32_t a);
     void        error(UErrorCode e);                   // error reporting convenience function.
     void        fixOpStack(RBBINode::OpPrecedence p);
                                                        //   a character.
diff --git a/icu4c/source/common/triedict.cpp b/icu4c/source/common/triedict.cpp
index 4983e9cd2d8..db1c8ebdcc0 100644
--- a/icu4c/source/common/triedict.cpp
+++ b/icu4c/source/common/triedict.cpp
@@ -1,7 +1,7 @@
 /**
  *******************************************************************************
- * Copyright (C) 2006, International Business Machines Corporation and others. *
- * All Rights Reserved.                                                        *
+ * Copyright (C) 2006-2007, International Business Machines Corporation        *
+ * and others. All Rights Reserved.                                            *
  *******************************************************************************
  */
 
@@ -820,7 +820,7 @@ compactOneNode(const TernaryNode *node, UBool parentEndsWord, UStack &nodes, UEr
         if (vResult == NULL) {
             status = U_MEMORY_ALLOCATION_ERROR;
         }
-        if (U_SUCCESS(status)) {
+        else if (U_SUCCESS(status)) {
             UBool   endsWord = FALSE;
             // Take up nodes until we end a word, or hit a node with < or > links
             do {
diff --git a/icu4c/source/common/usprep.cpp b/icu4c/source/common/usprep.cpp
index 00f4788d884..12d51be3caa 100644
--- a/icu4c/source/common/usprep.cpp
+++ b/icu4c/source/common/usprep.cpp
@@ -1,7 +1,7 @@
 /*
  *******************************************************************************
  *
- *   Copyright (C) 2003-2006, International Business Machines
+ *   Copyright (C) 2003-2007, International Business Machines
  *   Corporation and others.  All Rights Reserved.
  *
  *******************************************************************************
@@ -445,7 +445,7 @@ uprv_syntaxError(const UChar* rules,
     parseError->line = 0 ; // we are not using line numbers 
     
     // for pre-context
-    int32_t start = (pos <=U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1));
+    int32_t start = (pos < U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1));
     int32_t limit = pos;
     
     u_memcpy(parseError->preContext,rules+start,limit-start);
diff --git a/icu4c/source/i18n/format.cpp b/icu4c/source/i18n/format.cpp
index e93642c6ade..883a41d575e 100644
--- a/icu4c/source/i18n/format.cpp
+++ b/icu4c/source/i18n/format.cpp
@@ -1,6 +1,6 @@
 /*
 *******************************************************************************
-* Copyright (C) 1997-2004, International Business Machines Corporation and    *
+* Copyright (C) 1997-2007, International Business Machines Corporation and    *
 * others. All Rights Reserved.                                                *
 *******************************************************************************
 *
@@ -152,7 +152,7 @@ void Format::syntaxError(const UnicodeString& pattern,
     parseError.line=0;  // we are not using line number
     
     // for pre-context
-    int32_t start = (pos <=U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1
+    int32_t start = (pos < U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1
                                                              /* subtract 1 so that we have room for null*/));
     int32_t stop  = pos;
     pattern.extract(start,stop-start,parseError.preContext,0);
diff --git a/icu4c/source/i18n/ucol.cpp b/icu4c/source/i18n/ucol.cpp
index ff9d42e99da..96726a2559a 100644
--- a/icu4c/source/i18n/ucol.cpp
+++ b/icu4c/source/i18n/ucol.cpp
@@ -5529,6 +5529,8 @@ ucol_nextSortKeyPart(const UCollator *coll,
         count<0 || (count>0 && dest==NULL)
     ) {
         *status=U_ILLEGAL_ARGUMENT_ERROR;
+        UTRACE_EXIT_STATUS(status);
+        return 0;
     }
 
     UTRACE_DATA6(UTRACE_VERBOSE, "coll=%p, iter=%p, state=%d %d, dest=%p, count=%d",
diff --git a/icu4c/source/i18n/ucol_tok.cpp b/icu4c/source/i18n/ucol_tok.cpp
index 83528582229..8a8ea4455ae 100644
--- a/icu4c/source/i18n/ucol_tok.cpp
+++ b/icu4c/source/i18n/ucol_tok.cpp
@@ -172,7 +172,7 @@ void syntaxError(const UChar* rules,
     parseError->line = 0 ; /* we are not using line numbers */
 
     // for pre-context
-    int32_t start = (pos <=U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1));
+    int32_t start = (pos < U_PARSE_CONTEXT_LEN)? 0 : (pos - (U_PARSE_CONTEXT_LEN-1));
     int32_t stop  = pos;
 
     u_memcpy(parseError->preContext,rules+start,stop-start);
diff --git a/icu4c/source/io/locbund.c b/icu4c/source/io/locbund.c
index fd4935842a3..1859999b158 100644
--- a/icu4c/source/io/locbund.c
+++ b/icu4c/source/io/locbund.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 1998-2006, International Business Machines
+*   Copyright (C) 1998-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -162,7 +162,7 @@ UNumberFormat*
 u_locbund_getNumberFormat(ULocaleBundle *bundle, UNumberFormatStyle style)
 {
     UNumberFormat *formatAlias = NULL;
-    if (style >= UNUM_IGNORE) {
+    if (style > UNUM_IGNORE) {
         formatAlias = bundle->fNumberFormat[style-1];
         if (formatAlias == NULL) {
             if (bundle->isInvariantLocale) {
diff --git a/icu4c/source/tools/ctestfw/uperf.cpp b/icu4c/source/tools/ctestfw/uperf.cpp
index 05a8839e677..5b2dbe667b0 100644
--- a/icu4c/source/tools/ctestfw/uperf.cpp
+++ b/icu4c/source/tools/ctestfw/uperf.cpp
@@ -439,12 +439,16 @@ UBool UPerfTest::runTestLoop( char* testname, char* par )
             }
             if(verbose && U_SUCCESS(status)) {
                 double avg_t = sum_t/passes;
-                if(events == -1) {
+                if (loops == 0 || ops == 0) {
+                    fprintf(stderr, "%s did not run\n", name);
+                }
+                else if(events == -1) {
                     fprintf(stdout, "%%= %s avg: %.4g loops: %i avg/op: %.4g ns\n",
                             name, avg_t, (int)loops, (avg_t*1E9)/(loops*ops));
                     fprintf(stdout, "_= %s min: %.4g loops: %i min/op: %.4g ns\n",
                             name, min_t, (int)loops, (min_t*1E9)/(loops*ops));
-                } else {
+                }
+                else {
                     fprintf(stdout, "%%= %s avg: %.4g loops: %i avg/op: %.4g ns avg/event: %.4g ns\n",
                             name, avg_t, (int)loops, (avg_t*1E9)/(loops*ops), (avg_t*1E9)/(loops*events));
                     fprintf(stdout, "_= %s min: %.4g loops: %i min/op: %.4g ns min/event: %.4g ns\n",
diff --git a/icu4c/source/tools/gencase/store.c b/icu4c/source/tools/gencase/store.c
index c4d241eed45..90d3abf8d71 100644
--- a/icu4c/source/tools/gencase/store.c
+++ b/icu4c/source/tools/gencase/store.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2004-2005, International Business Machines
+*   Copyright (C) 2004-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -266,7 +266,7 @@ addUnfolding(UChar32 c, const UChar *s, int32_t length) {
                 (long)length, UGENCASE_UNFOLD_STRING_WIDTH);
         exit(U_INTERNAL_PROGRAM_ERROR);
     }
-    if(unfoldTop>=LENGTHOF(unfold)) {
+    if(unfoldTop >= (LENGTHOF(unfold) - UGENCASE_UNFOLD_STRING_WIDTH)) {
         fprintf(stderr, "gencase error: too many multi-character case foldings\n");
         exit(U_BUFFER_OVERFLOW_ERROR);
     }
diff --git a/icu4c/source/tools/genuca/genuca.cpp b/icu4c/source/tools/genuca/genuca.cpp
index 8a0f87180c9..8fb29b4aa2a 100644
--- a/icu4c/source/tools/genuca/genuca.cpp
+++ b/icu4c/source/tools/genuca/genuca.cpp
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2000-2006, International Business Machines
+*   Copyright (C) 2000-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -473,8 +473,8 @@ UCAElements *readAnElement(FILE *data, tempUCATable *t, UCAConstants *consts, UE
     // Directives.
     if(buffer[0] == '[') {
       uint32_t cnt = 0;
-      struct {
-        char name[256];
+      static const struct {
+        char name[128];
         uint32_t *what;
         ActionType what_to_do;
       } vt[]  = { {"[first tertiary ignorable",  consts->UCA_FIRST_TERTIARY_IGNORABLE,  READCE},
@@ -682,13 +682,19 @@ UCAElements *readAnElement(FILE *data, tempUCATable *t, UCAConstants *consts, UE
     element->isThai = UCOL_ISTHAIPREVOWEL(element->cPoints[0]);
 #endif
     // we don't want any strange stuff after useful data!
-    while(pointer < commentStart)  {
-        if(*pointer != ' ' && *pointer != '\t')
-        {
-            *status=U_INVALID_FORMAT_ERROR;
-            break;
+    if (pointer == NULL) {
+        /* huh? Did we get ']' without the '['? Pair your brackets! */
+        *status=U_INVALID_FORMAT_ERROR;
+    }
+    else {
+        while(pointer < commentStart)  {
+            if(*pointer != ' ' && *pointer != '\t')
+            {
+                *status=U_INVALID_FORMAT_ERROR;
+                break;
+            }
+            pointer++;
         }
-        pointer++;
     }
 
     if(U_FAILURE(*status)) {
diff --git a/icu4c/source/tools/icuswap/icuswap.cpp b/icu4c/source/tools/icuswap/icuswap.cpp
index 2fb331995be..a5295df651f 100644
--- a/icu4c/source/tools/icuswap/icuswap.cpp
+++ b/icu4c/source/tools/icuswap/icuswap.cpp
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2003-2006, International Business Machines
+*   Copyright (C) 2003-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -42,6 +42,7 @@
 /* definitions */
 
 #define LENGTHOF(array) (int32_t)(sizeof(array)/sizeof((array)[0]))
+#define DEFAULT_PADDING_LENGTH 15
 
 static UOption options[]={
     UOPTION_HELP_H,
@@ -170,7 +171,7 @@ main(int argc, char *argv[]) {
     }
 
     length=fileSize(in);
-    if(length<=0) {
+    if(length<DEFAULT_PADDING_LENGTH) {
         fprintf(stderr, "%s: empty input file \"%s\"\n", pname, argv[1]);
         rc=2;
         goto done;
@@ -182,7 +183,7 @@ main(int argc, char *argv[]) {
      * because the last item may be resorted into the middle and then needs
      * additional padding bytes
      */
-    data=(char *)malloc(length+15);
+    data=(char *)malloc(length+DEFAULT_PADDING_LENGTH);
     if(data==NULL) {
         fprintf(stderr, "%s: error allocating memory for \"%s\"\n", pname, argv[1]);
         rc=2;
@@ -190,7 +191,7 @@ main(int argc, char *argv[]) {
     }
 
     /* set the last 15 bytes to the usual padding byte, see udata_swapPackage() */
-    uprv_memset(data+length-15, 0xaa, 15);
+    uprv_memset(data+length-DEFAULT_PADDING_LENGTH, 0xaa, DEFAULT_PADDING_LENGTH);
 
     if(length!=(int32_t)fread(data, 1, length, in)) {
         fprintf(stderr, "%s: error reading \"%s\"\n", pname, argv[1]);
@@ -519,7 +520,7 @@ udata_swapPackage(const char *inFilename, const char *outFilename,
          */
         if(inData==outData) {
             /* +15: prepare for extra padding of a newly-last item */
-            table=(ToCEntry *)uprv_malloc(itemCount*sizeof(ToCEntry)+length+15);
+            table=(ToCEntry *)uprv_malloc(itemCount*sizeof(ToCEntry)+length+DEFAULT_PADDING_LENGTH);
             if(table!=NULL) {
                 outBytes=(uint8_t *)(table+itemCount);
 
@@ -533,7 +534,7 @@ udata_swapPackage(const char *inFilename, const char *outFilename,
         if(table==NULL) {
             udata_printError(ds, "udata_swapPackage(): out of memory allocating %d bytes\n",
                              inData==outData ?
-                                 itemCount*sizeof(ToCEntry)+length+15 :
+                                 itemCount*sizeof(ToCEntry)+length+DEFAULT_PADDING_LENGTH :
                                  itemCount*sizeof(ToCEntry));
             *pErrorCode=U_MEMORY_ALLOCATION_ERROR;
             return 0;
diff --git a/icu4c/source/tools/pkgdata/pkgtypes.c b/icu4c/source/tools/pkgdata/pkgtypes.c
index 97f3ff51c36..8282b79d5b4 100644
--- a/icu4c/source/tools/pkgdata/pkgtypes.c
+++ b/icu4c/source/tools/pkgdata/pkgtypes.c
@@ -1,6 +1,6 @@
 /**************************************************************************
 *
-*   Copyright (C) 2000-2006, International Business Machines
+*   Copyright (C) 2000-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ***************************************************************************
@@ -223,7 +223,7 @@ CharList *pkg_appendUniqueDirToList(CharList *l, CharList** end, const char *str
     if(!rPtr) {
         return l; /* no dir path */
     }
-    if((rPtr-strAlias) > (sizeof(aBuf)/sizeof(aBuf[0]))) {
+    if((rPtr-strAlias) >= (sizeof(aBuf)/sizeof(aBuf[0]))) {
         fprintf(stderr, "## ERR: Path too long [%d chars]: %s\n", (int)sizeof(aBuf), strAlias);
         return l;
     }
diff --git a/icu4c/source/tools/toolutil/writesrc.c b/icu4c/source/tools/toolutil/writesrc.c
index a53bb4b2d86..28303c733e5 100644
--- a/icu4c/source/tools/toolutil/writesrc.c
+++ b/icu4c/source/tools/toolutil/writesrc.c
@@ -1,7 +1,7 @@
 /*
 *******************************************************************************
 *
-*   Copyright (C) 2005, International Business Machines
+*   Copyright (C) 2005-2007, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 *******************************************************************************
@@ -72,7 +72,7 @@ usrc_create(const char *path, const char *filename) {
         fprintf(
             stderr,
             "usrc_create(%s, %s): unable to create file\n",
-            path!=NULL ? path : NULL, filename);
+            path!=NULL ? path : "", filename);
     }
     return f;
 }