About changing password with exchange account

Hi, exchange connector developers,

I built my evolution with MIT kerberos support. However, when I try to
change my password using the change password button in the account
editor, it failed. Looking into the code, I found that
krb5_get_init_creds_password in get_init_cred in
evolution-data-server/servers/exchange/lib/e2k_kerberos.c returns
KRB5_REALM_UNKNOWN. 

I guess there may be some problems in the exchange server realm
settings. How to find the realm name of the Exchange server? BTW, I can
access the Exchange server machine.

Any advice?

Thanks. 

--Irene