Thanks for the excellent critique, Oliver, where I learned some things. To be complete about this and maybe more helpful to some other noob, I didn't get milter-greylist from an rpm, I'd used yum install milter-greylist and it resolved the dependencies, but it gave me the non-standard pipe location to paste into sendmail.mc...
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Re: Install trouble - milter-greylist.sock missing
2007-03-19 by gsxatvcu