diff --git a/git_config.py b/git_config.py
index 32879ec..6ab286e 100644
--- a/git_config.py
+++ b/git_config.py
@@ -634,6 +634,9 @@
 
     if not rev.startswith('refs/'):
       rev = R_HEADS + rev
+    # ugly workaround
+    if rev.startswith('refs/builds/'):
+        return RefSpec(True, 'refs/builds/*', 'refs/builds/*').MapSource(rev)
 
     for spec in self.fetch:
       if spec.SourceMatches(rev):