samba - Sep 2003 - Forcing Kerberos from Pam/Winbind samba-3.0.0rc4

What is required to force Kerberos authentication from
Pam->Winbind? See winbindd log below - common
operations like wbinfo -u work fine.

Connecting to 10.99.100.205 at port 445
Doing spnego session setup (blob length=123)
got OID=1 2 840 48018 1 2 2
got OID=1 2 840 113554 1 2 2
got OID=1 2 840 113554 1 2 2 3
got OID=1 3 6 1 4 1 311 2 2 10
got principal=fmsamrvm002$@AMRVM.CORPVM.SMITHCO.COM
Doing kerberos session setup
Advancing clock by 7 seconds to cope with clock skew
signing_good: SMB signature check failed on seq 1!
SMB Signature verification failed on incoming packet!
failed kerberos session setup with NT_STATUS_OK
failed anonymous session setup with NT_STATUS_OK
[14342]: request interface version
[14342]: request location of privileged pipe
[14342]: pam auth amrvm\ssmith315
get_trust_pw: could not fetch trust account password
for my domain AMRVM
Plain-text authentication for user amrvm\ssmith315
returned NT_STATUS_CANT_ACCESS_DOMAIN_INFO (PAM: 4)