diff --git a/runbot/runbot.py b/runbot/runbot.py
index b01a190d..b6913836 100644
--- a/runbot/runbot.py
+++ b/runbot/runbot.py
@@ -271,7 +271,7 @@ def update_git(self, cr, uid, repo, context=None):
         git_refs = git_refs.strip()
 
         refs = [[decode_utf(field) for field in line.split('\x00')] for line in git_refs.split('\n')]
-
+        refs = [ref for ref in refs if len(ref) == 8]  # cleanup empty lines which cause unpack errors below
         for name, sha, date, author, author_email, subject, committer, committer_email in refs:
             # create or get branch
             branch_ids = Branch.search(cr, uid, [('repo_id', '=', repo.id), ('name', '=', name)])