SVN commit 1081285 by lmurray:

If the loaded decoration library isn't a valid decoration load the
default decoration instead of dying.
CCBUG: 224440


 M  +8 -0      kdecoration_plugins_p.cpp  


--- trunk/KDE/kdebase/workspace/kwin/lib/kdecoration_plugins_p.cpp #1081284:1081285
@@ -137,6 +137,7 @@
     library = new KLibrary(path);
 
     // If that fails, fall back to the default plugin
+trydefaultlib:
     if (!library)
         {
 	kDebug(1212) << " could not load library, try default plugin again";
@@ -162,6 +163,13 @@
 
     if(!create_ptr)
         {
+        if( nameStr != defaultPlugin )
+            {
+            kDebug(1212) << i18n( "The library %1 is not a KWin plugin.", path );
+            library->unload();
+            library = NULL;
+            goto trydefaultlib;
+            }
         error( i18n( "The library %1 is not a KWin plugin.", path ));
         library->unload();
         return false;