major problem with ntlm_auth and winbindd pipe

Hi All, I use freeradius for peap-authentication and I have multiple samba/winbind services to authenticate against to different ADs. In my setup I use a perlscript to start the right winbindd for a request. Now I have the problem that the winbind-pipe sometime dies. Has anyone experiences with dieing winbind-pipes in a freeradius peap environment? Can anyone help me? Lukas