--- a/mercurial/patch.py	Fri Apr 09 15:14:43 2010 +0200
+++ b/mercurial/patch.py	Fri Apr 09 20:34:05 2010 +0200
@@ -47,6 +47,9 @@
         if inheader and line[0] in (' ', '\t'):
             # continuation
             return True
+        if line[0] in (' ', '-', '+'):
+            # diff line - don't check for header pattern in there
+            return False
         l = line.split(': ', 1)
         return len(l) == 2 and ' ' not in l[0]