fix problem with bounce-message if incoming mail has insufficient privilege... ...e.g., user not existing (issue 2550534) Added a regression test for this issue that reproduces the traceback reported in issue 2550534 I'm using a slightly modified variant of the original patch that avoids repeated string-concatenation (which could degenerate to quadratic runtime behaviour for large number of email headers).

#!/usr/bin/env python
import zlib, base64, sys
print base64.encodestring(zlib.compress(sys.stdin.read()))