Milter-greylist

i recently upgraded to 4.2.6 with no troubles. i then installed it fresh
on a new system and sendmail wouldn't start.  i tracked it down to a
trailing comma in the sendmail.cf left there by the milter-greylist.m4
config file.  the update didn't get triggered because the sendmail cf
logic isn't smart enough to rebuild if a feature file changes.

i'm working on a tweak to the m4 to deal with this, but wanted to give a
heads up to folks.