Change into the newly created "mod_auth_ldap" directory, and configure the module itself (some parts of the sha algorithm are endian-dependent, and endianess is not checked by the Apache configure script, so the module comes with it's own autoconf script).
% cd mod_auth_ldap; ./configure
Now it's time to choose your favorite apache Config options, and additionally activate the LDAP authentication module.
% cd ../../..; ./configure --prefix=/var/apps/apache \
--activate-module=src/modules/mod_auth_ldap/mod_auth_ldap.c
After Apache has been configured to your choice, make and install it as usual:
% make
[ build messages deleted ]
% make install