There's a closed pull request on the mblaze repository

mcom: quote sequence for mbnc and mrep
https://github.com/leahneukirchen/mblaze/pull/231

Description:
I was getting the "mrep: needs exactly one mail to reply to" error when trying to reply to messages, where the file was located in a directory with spaces. With this change, I was able to use `mrep` in such a case. I noticed the same code in `mbnc`, so I also applied the change there.