diff --git a/submittodebian b/submittodebian
index 2238521..13a5bc1 100755
--- a/submittodebian
+++ b/submittodebian
@@ -239,7 +239,7 @@ def main():
 
     tmpdir = mkdtemp()
     body = os.path.join(tmpdir, 'bug_body')
-    with open(body, 'w', encoding='utf-8') as f:
+    with open(body, 'wb') as f:
         f.write(bug_body.encode('utf-8'))
 
     restore_maintainer('debian')