Configure fixes from Hans de Graaff, as used in Gentoo. 2008-01-17 Aidan Kehoe <kehoea@parhasard.net> * configure.ac: If using a version of the gdbm library that sticks dbm_open in libgdbm_compat.so, also link to that library. Correct a thinko with DBM version 4 checks. Both from Hans de Graaff, in http://mid.gmane.org/20050812092756.6850.qmail@graaff.xs4all.nl and http://mid.gmane.org/pan.2007.06.24.10.10.57@gentoo.org; thank you Hans! * configure: Regenerate.