diff --git a/spring-core/src/main/java/org/springframework/util/StringUtils.java b/spring-core/src/main/java/org/springframework/util/StringUtils.java
index 3e1960870fc0..c44c0c4ca7e5 100644
--- a/spring-core/src/main/java/org/springframework/util/StringUtils.java
+++ b/spring-core/src/main/java/org/springframework/util/StringUtils.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2011 the original author or authors.
+ * Copyright 2002-2012 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -674,7 +674,7 @@ public static Locale parseLocaleString(String localeString) {
 		if (parts.length >= 2) {
 			// There is definitely a variant, and it is everything after the country
 			// code sans the separator between the country code and the variant.
-			int endIndexOfCountryCode = localeString.indexOf(country) + country.length();
+			int endIndexOfCountryCode = localeString.lastIndexOf(country) + country.length();
 			// Strip off any leading '_' and whitespace, what's left is the variant.
 			variant = trimLeadingWhitespace(localeString.substring(endIndexOfCountryCode));
 			if (variant.startsWith("_")) {
diff --git a/spring-core/src/test/java/org/springframework/util/StringUtilsTests.java b/spring-core/src/test/java/org/springframework/util/StringUtilsTests.java
index 65cf24272493..b366ed7f96d0 100644
--- a/spring-core/src/test/java/org/springframework/util/StringUtilsTests.java
+++ b/spring-core/src/test/java/org/springframework/util/StringUtilsTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2011 the original author or authors.
+ * Copyright 2002-2012 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -639,4 +639,11 @@ public void testParseLocaleWithInvalidCharacters() {
 		}
 	}
 
+	/**
+	 * See SPR-9420.
+	 */
+	public void testParseLocaleWithSameLowercaseTokenForLanguageAndCountry() {
+		assertEquals("tr_TR", StringUtils.parseLocaleString("tr_tr").toString());
+		assertEquals("bg_BG_vnt", StringUtils.parseLocaleString("bg_bg_vnt").toString());
+	}
 }