diff --git a/icu4c/source/i18n/dtitvinf.cpp b/icu4c/source/i18n/dtitvinf.cpp
index 51f2d00fe64..bd6d3f9f47b 100644
--- a/icu4c/source/i18n/dtitvinf.cpp
+++ b/icu4c/source/i18n/dtitvinf.cpp
@@ -1,5 +1,5 @@
 /*******************************************************************************
-* Copyright (C) 2008-2014, International Business Machines Corporation and
+* Copyright (C) 2008-2015, International Business Machines Corporation and
 * others. All Rights Reserved.
 *******************************************************************************
 *
@@ -223,7 +223,7 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& err)
   char parentLocale[ULOC_FULLNAME_CAPACITY];
   uprv_strcpy(parentLocale, locName);
   UErrorCode status = U_ZERO_ERROR;
-  Hashtable skeletonSet(FALSE, status);
+  Hashtable skeletonKeyPairs(FALSE, status);
   if ( U_FAILURE(status) ) {
       return;
   }
@@ -277,10 +277,6 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& err)
                     continue;
                 }
                 UnicodeString skeletonUniStr(skeleton, -1, US_INV);
-                if ( skeletonSet.geti(skeletonUniStr) == 1 ) {
-                    continue;
-                }
-                skeletonSet.puti(skeletonUniStr, 1, status);
                 if ( uprv_strcmp(skeleton, gFallbackPatternTag) == 0 ) {
                     continue;  // fallback
                 }
@@ -304,6 +300,12 @@ DateIntervalInfo::initializeData(const Locale& locale, UErrorCode& err)
                     if ( U_FAILURE(status) ) {
                         break;
                     }
+                    UnicodeString keyUniStr(key, -1, US_INV);
+                    UnicodeString skeletonKeyPair(skeletonUniStr + keyUniStr);
+                    if ( skeletonKeyPairs.geti(skeletonKeyPair) == 1 ) {
+                        continue;
+                    }
+                    skeletonKeyPairs.puti(skeletonKeyPair, 1, status);
         
                     UCalendarDateFields calendarField = UCAL_FIELD_COUNT;
                     if ( !uprv_strcmp(key, "y") ) {
diff --git a/icu4c/source/test/intltest/dtifmtts.cpp b/icu4c/source/test/intltest/dtifmtts.cpp
index a9dc8b5caaf..31c4b712388 100644
--- a/icu4c/source/test/intltest/dtifmtts.cpp
+++ b/icu4c/source/test/intltest/dtifmtts.cpp
@@ -49,6 +49,7 @@ void DateIntervalFormatTest::runIndexedTest( int32_t index, UBool exec, const ch
         TESTCASE(3, testSetIntervalPatternNoSideEffect);
         TESTCASE(4, testYearFormats);
         TESTCASE(5, testStress);
+        TESTCASE(6, testTicket11583_2);
         default: name = ""; break;
     }
 }
@@ -1509,4 +1510,24 @@ void DateIntervalFormatTest::stress(const char** data, int32_t data_length,
     }
 }
 
+void DateIntervalFormatTest::testTicket11583_2() {
+    UErrorCode status = U_ZERO_ERROR;
+    LocalPointer<DateIntervalFormat> fmt(
+            DateIntervalFormat::createInstance("yMMM", "es-US", status));
+    if (!assertSuccess("Error create format object", status)) {
+        return;
+    }
+    DateInterval interval((UDate) 1232364615000.0, (UDate) 1328787015000.0);
+    UnicodeString appendTo;
+    FieldPosition fpos(FieldPosition::DONT_CARE);
+    UnicodeString expected("ene. de 2009 \u2013 feb. de 2012");
+    assertEquals(
+            "",
+            expected.unescape(),
+            fmt->format(&interval, appendTo, fpos, status));
+    if (!assertSuccess("Error formatting", status)) {
+        return;
+    }
+}
+
 #endif /* #if !UCONFIG_NO_FORMATTING */
diff --git a/icu4c/source/test/intltest/dtifmtts.h b/icu4c/source/test/intltest/dtifmtts.h
index 8e6faf0c597..3d50f72e6a3 100644
--- a/icu4c/source/test/intltest/dtifmtts.h
+++ b/icu4c/source/test/intltest/dtifmtts.h
@@ -1,6 +1,6 @@
 /********************************************************************
  * COPYRIGHT: 
- * Copyright (c) 2008-2013 International Business Machines Corporation and
+ * Copyright (c) 2008-2015 International Business Machines Corporation and
  * others. All Rights Reserved.
  ********************************************************************/
 
@@ -52,6 +52,8 @@ public:
      */
     void testStress();
 
+    void testTicket11583_2();
+
 private:
     /**
      * Test formatting against expected result