(upstream... ) Jaymale courier-imap-4.0.4 # find -name configure ./md5/configure ./imap/configure ./sha1/configure ./tcpd/configure ./rfc1035/configure ./rfc2045/configure ./configure ./libhmac/configure ./liblock/configure ./maildir/configure ./makedat/configure ./soxwrap/configure ./bdbobj/configure ./random128/configure ./gdbmobj/configure ./numlib/configure ./rfc822/configure ./unicode/configure ./waitlib/configure Jaymale courier-imap-4.0.4 # find -name configure|wc -l 19 It takes about 49 minutes to emerge courier-imap, it takes about 4 minutes to actually compile. the entire rest of the time is spent running configure 19 times. i -don't think- $arch changed underneath it from the top level configure.
Not a Gentoo problem, and not a bug either. http://www.courier-mta.org/FAQ.html#configloop