Index: /trunk/src/org/openstreetmap/josm/tools/Logging.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/tools/Logging.java	(revision 11623)
+++ /trunk/src/org/openstreetmap/josm/tools/Logging.java	(revision 11624)
@@ -70,5 +70,5 @@
 
             @Override
-            public void publish(LogRecord record) {
+            public synchronized void publish(LogRecord record) {
                 if (!stderr.isLoggable(record)) {
                     super.publish(record);