diff --git a/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/sql/AbstractDB2Dictionary.java b/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/sql/AbstractDB2Dictionary.java
index 22af396ea..5000e8ac3 100644
--- a/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/sql/AbstractDB2Dictionary.java
+++ b/openjpa-jdbc/src/main/java/org/apache/openjpa/jdbc/sql/AbstractDB2Dictionary.java
@@ -31,9 +31,13 @@ public abstract class AbstractDB2Dictionary
         longVarbinaryTypeName = "BLOB";
         varbinaryTypeName = "BLOB";
 
+        // DB2-based databases have restrictions on having uncast parameters
+        // in string functions
         toUpperCaseFunction = "UPPER(CAST({0} AS VARCHAR(1000)))";
         toLowerCaseFunction = "LOWER(CAST({0} AS VARCHAR(1000)))";
         stringLengthFunction = "LENGTH(CAST({0} AS VARCHAR(1000)))";
+        concatenateFunction = "(CAST({0} AS VARCHAR(1000)))||"
+            + "(CAST({1} AS VARCHAR(1000)))";
 
         trimLeadingFunction = "LTRIM({0})";
         trimTrailingFunction = "RTRIM({0})";