Comment 3 for bug 1304953

The problem doesn't seem to be in apache-mod-auth-ntlm-winbind - there are no relevant matches for "pipe" in either the source code of the package or in the output of "strings /usr/lib/apache2/modules/mod_auth_ntlm_winbind.so".

This module is really just glue code for apache - it uses the /usr/bin/ntlm_auth helper in the winbind package to do the actual authentication, so I would suggest looking there.

(Although I'm the maintainer of this package in Debian, I no longer have access to a suitable environment to test it in - we were using it in a client project, but switched to kerberos auth a while back).