Index: /branches/release-35/lib/MT/Mail.pm
===================================================================
--- /branches/release-35/lib/MT/Mail.pm (revision 1680)
+++ /branches/release-35/lib/MT/Mail.pm (revision 1907)
@@ -79,4 +79,6 @@
     $hdrs{'MIME-Version'} ||= "1.0";
 
+    $hdrs{From} = $mgr->EmailAddressMain unless exists $hdrs{From};
+
     return 1 unless
         MT->run_callbacks('mail_filter', args => $hdrs_arg, headers => \%hdrs,