Index: trunk/src/org/openstreetmap/josm/gui/oauth/RetrieveRequestTokenTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/oauth/RetrieveRequestTokenTask.java	(revision 9353)
+++ trunk/src/org/openstreetmap/josm/gui/oauth/RetrieveRequestTokenTask.java	(revision 9354)
@@ -15,4 +15,5 @@
 import org.openstreetmap.josm.gui.PleaseWaitRunnable;
 import org.openstreetmap.josm.gui.help.HelpUtil;
+import org.openstreetmap.josm.gui.util.GuiHelper;
 import org.openstreetmap.josm.io.OsmTransferCanceledException;
 import org.openstreetmap.josm.io.OsmTransferException;
@@ -81,7 +82,12 @@
         } catch (OsmTransferCanceledException e) {
             return;
-        } catch (OsmOAuthAuthorizationException e) {
+        } catch (final OsmOAuthAuthorizationException e) {
             Main.error(e);
-            alertRetrievingRequestTokenFailed(e);
+            GuiHelper.runInEDT(new Runnable() {
+                @Override
+                public void run() {
+                    alertRetrievingRequestTokenFailed(e);
+                }
+            });
             requestToken = null;
         } finally {