SASL LDAP binding over IPv6

[Xu, Qiang (FXSGSC)]

Hi, all: 

Overall, my implementation of SASL binding is OK, but it doesn't work in dealing with IPv6:
====================================================================
<apManager> (Thu Jun 04 2009 15:04:32.847) <p3593,t824878304,aba_ldap_interface.c,1470>
     INFO>> primary server IP address is 2001:4898:e0:f04b:21f:29ff:fee2:b390
......
<apManager> (Thu Jun 04 2009 15:04:32.851) <p3593,t824878304,aba_ldap_interface.c,1717>
     INFO>> SASL Login
<apManager> (Thu Jun 04 2009 15:04:32.852) <p3593,t824878304,aba_ldap_interface.c,1833>
     INFO>> SASL LDAP BIND with GSSAPI: Value of ldapStatus 91 
<apManager> (Thu Jun 04 2009 15:04:32.852) <p3593,t824878304,aba_ldap_interface.c,1840>
    ERROR>> LDAP BIND: Value of ldap failure status and text 91 Can't connect to the LDAP server 
====================================================================
>From what I can gather from googling, this error 91 is mainly about certificates in TLS/SSL connection. But I am not using either of them now. 

And there is no outward SASL traffic. In contrast, if I am using simple binding to the same server with IPv6 address, everthing looks good. 

Is there anything worthy of note when IPv6 is used in SASL binding?

Looking forward to help,
Xu Qiang