This is the apache 2.x port of mod_auth_udp (for apache 1.x).
I have rewritten it to be used with recent apache versions.
<Directory "/jail/home">
AuthBasicProvider UDP
AuthUDPGetEnv $owner
AuthUDPHost 192.168.10.1
AuthUDPPort 2233
AuthUDPSendPassword Off
AuthUDPAuthoritative Off
AuthUDPEnable On
</Directory>