Index: trunk/src/org/openstreetmap/josm/io/OsmWriter.java
===================================================================
--- trunk/src/org/openstreetmap/josm/io/OsmWriter.java	(revision 1586)
+++ trunk/src/org/openstreetmap/josm/io/OsmWriter.java	(revision 1587)
@@ -24,4 +24,6 @@
 public class OsmWriter extends XmlWriter implements Visitor {
 
+    public final String DEFAULT_API_VERSION = "0.6";
+    
     /**
      * The counter for newly created objects. Starts at -1 and goes down.
@@ -43,5 +45,5 @@
         super(out);
         this.osmConform = osmConform;
-        this.version = version;
+        this.version = (version == null ? DEFAULT_API_VERSION : version);
     }