Verified. I broke Java 1.5 compatibility. I'll have to check, how to undo that. 
 
As first step, I'll just remove the breaking code. 
Here's a diff (since it seems I can't commit anymore).  
 Code:
 Index: src/main/java/phex/utils/InternalFileHandler.java
===================================================================
--- src/main/java/phex/utils/InternalFileHandler.java   (Revision 4144)
+++ src/main/java/phex/utils/InternalFileHandler.java   (Arbeitskopie)
@@ -66,14 +66,14 @@
                 // dont add already downloading or shared urns.
                 // If we've got a relativeDownloadDir, download to there.
-                if ( relativeDownloadDir.isEmpty() )
-                {
+                //if ( relativeDownloadDir.isEmpty() )
+                //{
                     downloadUri( uri );
-                }
-                else
-                {
+                //}
+                //else
+                //{
                     downloadUri( uri, relativeDownloadDir );
-                }
+                //}
             }
 /*            String uuri = parser.getUpdateURI();