diff --git a/mysql-test/r/udf.result b/mysql-test/r/udf.result
index c7a9b0982a9..bba722e523c 100644
--- a/mysql-test/r/udf.result
+++ b/mysql-test/r/udf.result
@@ -311,4 +311,27 @@ drop function f3;
 drop function metaphon;
 drop function myfunc_double;
 drop function myfunc_int;
+CREATE FUNCTION metaphon RETURNS STRING SONAME "UDF_EXAMPLE_LIB";
+create table t1 (a char);
+set GLOBAL query_cache_size=1355776;
+reset query cache;
+select metaphon('MySQL') from t1;
+metaphon('MySQL')
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	0
+show status like "Qcache_queries_in_cache";
+Variable_name	Value
+Qcache_queries_in_cache	0
+select metaphon('MySQL') from t1;
+metaphon('MySQL')
+show status like "Qcache_hits";
+Variable_name	Value
+Qcache_hits	0
+show status like "Qcache_queries_in_cache";
+Variable_name	Value
+Qcache_queries_in_cache	0
+drop table t1;
+drop function metaphon;
+set GLOBAL query_cache_size=default;
 End of 5.0 tests.
diff --git a/mysql-test/t/udf.test b/mysql-test/t/udf.test
index 7d870a86bc8..07a4a2d870b 100644
--- a/mysql-test/t/udf.test
+++ b/mysql-test/t/udf.test
@@ -340,4 +340,28 @@ drop function metaphon;
 drop function myfunc_double;
 drop function myfunc_int;
 
+#
+# Bug #28921: Queries containing UDF functions are cached
+#
+
+--replace_result $UDF_EXAMPLE_LIB UDF_EXAMPLE_LIB
+eval CREATE FUNCTION metaphon RETURNS STRING SONAME "$UDF_EXAMPLE_LIB";
+create table t1 (a char);
+
+set GLOBAL query_cache_size=1355776;
+reset query cache;
+
+select metaphon('MySQL') from t1;
+show status like "Qcache_hits";
+show status like "Qcache_queries_in_cache";
+
+select metaphon('MySQL') from t1;
+show status like "Qcache_hits";
+show status like "Qcache_queries_in_cache";
+
+drop table t1;
+drop function metaphon;
+set GLOBAL query_cache_size=default;
+
+
 --echo End of 5.0 tests.