Your bug report

#10077: 23.3; Rmail: rmail-summary-by-regexp doesn't work because of missing rmail-search-mime-header-function

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 10077@debbugs.gnu.org.

-- 
10077: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=10077
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