Milter-greylist

Question, is there a reason the regcomp calls in acl.c do not use the 
REG_EXTENDED flag?

I'm kind of used to modern extended regex syntax including things like ? 
and + that are not supported in basic posix regexes. I'm also not used to 
the "backwards" behavior of \( and \{ in basic regex, something which 
caused one of my rules to not match correctly.

I've since patched my copy of acl.c and recompiled, but I'm wondering if 
there was a reason to specifically use basic regex, a standard which even 
according to posix is obsolete and only exists for backward compatibility, 
instead of the more modern extended syntax.