Hi, I've published two patches which enable Cyrus imap and sasl to use the postgresql database as backend for mboxlist_db, quota_db, and authentication. You might download them from http://www.ogris.de/cyrus/. Unfortunately I was too lazy to patch the configure script and Makefile.in. So after applying these patches you have to call configure with LDFLAGS="-lpq" or even with appropriate CFLAGS & LDFLAGS if your postgresql headers and libs are in a non default location (sorry for that).
Felix PS: Feel free to import my patches into the main distributions :-)
