Bugzilla Bug 209679

When I trying to upgrade clamav and enabled the milter use flag, the emerge
process stopped and told me I had to install sendmail with the milter use flag.
First of all, this description is incorrect, for installing
mail-filter/libmilter should be suitable as well as installing sendmail. I in
fact did have libmilter installed. I found the line in the ebuild which caused
the error message to be shown, and it was as simple as an absolute path to the
library:
pkg_setup() {
        if use milter; then
                if [ ! -e /usr/lib/libmilter.a ] ; then
                        ewarn "In order to enable milter support, clamav needs
sendmail with enabled milter"
                        ewarn "USE flag. Either recompile sendmail with milter
USE flag enabled, or disable"
                        ewarn "this flag for clamav as well to disable milter
support."
                        die "need milter-enabled sendmail"
                fi
        fi
...

My libmilter.a is in /usr/lib64. 

Reproducible: Always

Steps to Reproduce:
1. Use a Gentoo system where /lib, /lib32, and /lib64 are segregated
2. Install libmilter (maybe this affects sendmail also?) (I had
mail-filter/libmilter-8.14.1-r1)
3. Attempt to install app-antivirus/clamav-0.92 (maybe other versions with
similar milter USE flag and libmilter support)

Actual Results:  
After attempting to install I had the error message about installing sendmail.
I got error message

Expected Results:  
I wanted the clamav package to be installed along with a milter

The software should have inherited some eclass or something, determined to look
in /usr/lib64 instead for libmilter, or have just depended on the DEPEND= logic
to make sure that either libmilter or sendmail with the milter flag are
installed.

Yes, the logic needs to be reworked a bit, now that there's also libmilter
available.
The lib vs. lib64 issue is easily resolved by get_libdir() function provided by
multilib eclass. I'll have a look at fixing it.

Fixed in CVS, also in newly added 0.92.1. Sorry about that!