Package: libmail-thread-perl
Version: 2.55-1
Severity: normal
Tags: upstream patch

Dear Maintainer,

With incomplete threads, It is possible to for the topmost subroutine to
return undef, so do not blindy assume the simple_subject call will be
made on a Mail::Thread::Container object.

Attached is a patch which avoids the issue by skipping as if the
subject were empty.

Note: upstream hasn't been responsive in years, but Cc-ing the RT
address at CPAN just in case.

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Debian Release: 7.8
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