Index: trunk/src/org/openstreetmap/josm/data/Preferences.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/Preferences.java	(revision 4810)
+++ trunk/src/org/openstreetmap/josm/data/Preferences.java	(revision 4811)
@@ -246,5 +246,5 @@
         path = System.getProperty("josm.home");
         if (path != null) {
-            preferencesDirFile = new File(path);
+            preferencesDirFile = new File(path).getAbsoluteFile();
         } else {
             path = System.getenv("APPDATA");