diff --git a/src/fr/devinsy/util/xml/XMLZipWriter.java b/src/fr/devinsy/util/xml/XMLZipWriter.java
index 63e4ac8..6cc2073 100644
--- a/src/fr/devinsy/util/xml/XMLZipWriter.java
+++ b/src/fr/devinsy/util/xml/XMLZipWriter.java
@@ -167,7 +167,7 @@ public class XMLZipWriter extends XMLWriter
 	{
 		if (fileName == null)
 		{
-			throw new NullPointerException("fileName is null.");
+			throw new IllegalArgumentException("fileName is null.");
 		}
 		else
 		{