Using the same setup as before, where modules was not failing to
build, I reconfiged using --with-modules=no --with-ldap=yes.
Configure works, but the resulting make fails because it cd's to
modules/ldap and runs make there. However, the gcc command doesn't
include -I../../src so config.h, lisp.h, and friends can't be found.
If you need more information, please ask.
Ray