if i remember correctly (i did this a few weeks ago just for testing) i got it built using::
./configure --without-threads --disable-dynamic
i think i had it throw errors when it came to the linking stage because the shared library handling in OS X seems to be kind of braindead (like e.g. one big flat namespace for symbol names for the application so it fails if two modules export the same symbol name etc.)
ld: common symbols not allowed with MH_DYLIB output format util-int.lo definition of common _ldap_int_resolv_mutex (size 4) /usr/bin/libtool: internal link edit command failed make[2]: *** [libldap_r.la] Error 1 make[1]: *** [all-common] Error 1 make: *** [all-common] Error 1