patch to compile with OpenLDAP 2.0.7

[Jeffrey C. O. <je...@ol...>]

I've gotten today's CVS version to compile against OpenLDAP 2.0.7.  It
seems that the OpenLDAP people dropped a number of macros between v1
and v2.  A fairly simple patch that #ifdefs the dropped macros and
everything compiles fine.  Oh yeah, I did have to use "LIBS=-lresolv
./configure" to get the configure script to properly: apparently the
RedHat RPM for OpenLDAP introduces a depencency because the configure
script fails with an undefined reference to __dn_expand and
__res_query.

I've attached the patch and also entered a bug on sourceforge.

Jeff