http://bugzilla.spamassassin.org/show_bug.cgi?id=4570
http://mail-archives.apache.org/mod_mbox/spamassassin-commits/200509.mbox/%3c20050910043552.60601.qmail@minotaur.apache.org%3e
Bug 4570 fix regexp to not segfault given large headers

diff -urN Mail-SpamAssassin-3.0.4.orig/lib/Mail/SpamAssassin/Message.pm Mail-SpamAssassin-3.0.4/lib/Mail/SpamAssassin/Message.pm
--- Mail-SpamAssassin-3.0.4.orig/lib/Mail/SpamAssassin/Message.pm	2005-06-05 15:31:23.000000000 -1000
+++ Mail-SpamAssassin-3.0.4/lib/Mail/SpamAssassin/Message.pm	2005-09-11 13:14:34.000000000 -1000
@@ -324,7 +324,7 @@
   my ($self, $hdr) = @_;
   
   return $self->{pristine_headers} unless $hdr;
-  my(@ret) = $self->{pristine_headers} =~ /^(?:$hdr:[ \t]+(.*\n(?:\s+\S.*\n)*))/mig;
+  my(@ret) = $self->{pristine_headers} =~ /^\Q$hdr\E:[ \t]+(.*?\n(?![ \t]))/smgi;
   if (@ret) {
     return wantarray ? @ret : $ret[-1];
   }