diff --git a/icu4c/source/common/locdispnames.cpp b/icu4c/source/common/locdispnames.cpp
index 1d86c0f828..dff49ce626 100644
--- a/icu4c/source/common/locdispnames.cpp
+++ b/icu4c/source/common/locdispnames.cpp
@@ -662,7 +662,7 @@ uloc_getDisplayName(const char *locale,
            if ( p0 != NULL && p1 != NULL ) { /* The pattern is well formed */
               if ( dest ) {
                   int32_t destLen = 0;
-                  UChar *result = (UChar *)uprv_malloc((length+1)*sizeof(UChar)); 
+                  UChar *result = (UChar *)uprv_malloc((length+1)*sizeof(UChar));
                   UChar *upos = (UChar *)dispLocPattern;
                   u_strcpy(result,dest);
                   dest[0] = 0;
@@ -684,7 +684,8 @@ uloc_getDisplayName(const char *locale,
                          destLen++;
                          dest[destLen] = 0; /* Null terminate */
                      }
-                  } 
+                  }
+                  length = destLen;
                   uprv_free(result);
               }
            }
diff --git a/icu4c/source/test/cintltst/cloctst.c b/icu4c/source/test/cintltst/cloctst.c
index a87644e18b..152688c517 100644
--- a/icu4c/source/test/cintltst/cloctst.c
+++ b/icu4c/source/test/cintltst/cloctst.c
@@ -240,6 +240,7 @@ void addLocaleTest(TestNode** root)
     TESTCASE(TestLikelySubtags);
     TESTCASE(TestToLanguageTag);
     TESTCASE(TestForLanguageTag);
+    TESTCASE(TestTrailingNull);
 }
 
 
@@ -2119,9 +2120,28 @@ static void TestGetBaseName(void) {
             return;
         }
     }
-
 }
 
+static void TestTrailingNull(void) {
+  const char* localeId = "zh_Hans";
+  UChar buffer[128]; /* sufficient for this test */
+  int32_t len;
+  UErrorCode status = U_ZERO_ERROR;
+  int i;
+
+  len = uloc_getDisplayName(localeId, localeId, buffer, 128, &status);
+  if (len > 128) {
+    log_err("buffer too small");
+    return;
+  }
+
+  for (i = 0; i < len; ++i) {
+    if (buffer[i] == 0) {
+      log_err("name contained null");
+      return;
+    }
+  }
+}
 
 /* Jitterbug 4115 */
 static void TestDisplayNameWarning(void) {
@@ -5536,4 +5556,3 @@ static void TestForLanguageTag(void) {
         }
     }
 }
-
diff --git a/icu4c/source/test/cintltst/cloctst.h b/icu4c/source/test/cintltst/cloctst.h
index 8c5e73c538..a544f31a02 100644
--- a/icu4c/source/test/cintltst/cloctst.h
+++ b/icu4c/source/test/cintltst/cloctst.h
@@ -1,6 +1,6 @@
 /********************************************************************
- * COPYRIGHT: 
- * Copyright (c) 1997-2009, International Business Machines Corporation and
+ * COPYRIGHT:
+ * Copyright (c) 1997-2010, International Business Machines Corporation and
  * others. All Rights Reserved.
  ********************************************************************/
 /********************************************************************************
@@ -89,6 +89,8 @@ static  void TestDisplayNames(void);
 
  static void TestGetBaseName(void);
 
+static void TestTrailingNull(void);
+
 static void TestGetLocale(void);
 
 /**