[Samba] Performance Problem / failed to verify PAC server signature

[Li, Ying (ESG)]

Hello,

We are experiencing ADS lower performance on Samba-3.0.22 for HPUX. I
did Google search, and find out one message posted at
http://lists.samba.org/archive/samba/2005-November/114231.html at the
earlier time. 

>From my observation, it seems there was a spin on
reply_spnego_negotiate()/ reply_spnego_kerberos() calls that invokes
register_vuid() to register uvid with different vuid# for a logon user
or a client. Finally, kill the intermediate vuid by
invalidate_vuid(vuid). This caused too many SMB calls on the wire(more
than hundreds of SMB calls, including
SMBsesssetup,SMBtcon,SMBtdis,SMBclose,SMBulogoff), but do nothing.

[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(251)
  ads_secrets_verify_ticket: enc type [18] failed to decrypt with error
Bad encryption type
[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(251)
  ads_secrets_verify_ticket: enc type [17] failed to decrypt with error
Bad encryption type
[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(251)
  ads_secrets_verify_ticket: enc type [16] failed to decrypt with error
Bad encryption type
[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(251)
  ads_secrets_verify_ticket: enc type [23] failed to decrypt with error
Bad encryption type
[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(251)
  ads_secrets_verify_ticket: enc type [1] failed to decrypt with error
Bad encryption type
[2007/08/14 12:01:03, 10]
libads/kerberos_verify.c:ads_secrets_verify_ticket(243)
  ads_secrets_verify_ticket: enc type [3] decrypted message !
......
 [2007/08/13 17:52:01, 3] libsmb/clikrb5.c:smb_krb5_verify_checksum(697)
    smb_krb5_verify_checksum: krb5_c_verify_checksum() failed: Bad
encryption type
 [2007/08/13 17:52:01, 2] libads/authdata.c:check_pac_checksum(659)
    check_pac_checksum: PAC Verification failed: Bad encryption type
(-1765328196)
 [2007/08/13 17:52:01, 0] libads/authdata.c:decode_pac_data(870)
    decode_pac_data: failed to verify PAC server signature
 [2007/08/13 17:52:01, 3]
libads/kerberos_verify.c:ads_verify_ticket(416)
    ads_verify_ticket: failed to decode PAC_DATA:
NT_STATUS_ACCESS_DENIED
......
[2007/08/14 12:01:05, 3] smbd/error.c:error_packet(142)
  error packet at smbd/sesssetup.c(318) cmd=115 (SMBsesssetupX)
NT_STATUS_LOGON_FAILURE
[2007/08/14 12:01:05, 3] smbd/sesssetup.c:reply_spnego_negotiate(558)
  reply_spnego_negotiate, invalidate_vuid

I'm wondering whether it's an abnormal behavior, or there is a specific
fix to improve performance. 
Could somebody look at this and help me out?

Thanks.
-Ying