diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/jlink/jlink.java b/src/main/org/apache/tools/ant/taskdefs/optional/jlink/jlink.java
index 899127b62..cc5492b5f 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/jlink/jlink.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/jlink/jlink.java
@@ -236,7 +236,7 @@ public class jlink extends Object{
         		    //In that case, just ignore the error and go on to the
         		    //next entry.
     		        String mess = ex.getMessage();
-    		        if (mess.indexOf("duplicate") > 0){
+    		        if (mess.indexOf("duplicate") >= 0){
     		            //It was the duplicate entry.
     		            continue;
     		        } else {