Debian has a newer version to get apache-2.4 support https://packages.debian.org/source/unstable/libapache2-mod-ldap-userdir
*mod_ldap_userdir-1.1.19 (18 Dec 2014) 18 Dec 2014; Michael Orlitzky <mjo@gentoo.org> +mod_ldap_userdir-1.1.19.ebuild: Version bump for apache-2.4.x support (bug #532832).