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--- a/Makefile.def.buildbot
+++ b/Makefile.def.buildbot
@@ -2,5 +2,5 @@
 
 buildbot_test:
 	./rebuild.bash
-	ln -s /usr/lib64/python2.7/site-packages/pysvn $(VIRTUAL_ENV)/lib/python2.7/site-packages/pysvn
+	-[ ! -f $(VIRTUAL_ENV)/lib/python2.7/site-packages/pysvn ] && ln -s /usr/lib64/python2.7/site-packages/pysvn $(VIRTUAL_ENV)/lib/python2.7/site-packages/
 	ALLURA_VALIDATION=none ./run_tests