Kerberos & jcifs

Question

I am developing a single sign-on module for our company's Intranet site. I am using jcfis extended version, which supports Kerberos authentication. It requires a krb5.ini file in c:/winnt directory. I am using AuthenticationFilter class which will autheticate a request. I have Tomcat on my machine and the main server is situated somewhere else, where the Kerberos is installed. When I am running my tomcat and opening page from my system, which has Tomcat, its running successfully, but when I am opening same page from other system, which is within the same domain, throwing an exception
"jcifs.spnego.AuthenticationException: Error performing Kerberos authentication:
java.lang.reflect.InvocationTargetException"
My C:/winnt/krb5.ini file:
[libdefaults]
     default_realm = IGGLOBAL.COM
     kdc_timesync = 1
     ccache_type = 4
     ticket_lifetime = 36000
     default_tkt_enctypes = rc4-hmac des3-hmac-sha1 des-cbc-crc
     default_tgs_enctypes = rc4-hmac des3-hmac-sha1 des-cbc-crc
     dns_lookup_kdc = true
     dns_lookup_realm = false
[domain_realm]
     .igglobal.com = IGGLOBAL.COM
[realms]     
     IGGLOBAL.COM = {
     kdc = 172.18.65.36:88
login = {
forwardable = true
krb5_run_aklog = true
krb5_get_tickets = true
[appdefaults]
     autologin = true
     forward = true
     forwardable = true
     encrypt = true
     useKeyTab=false
I am using Java 6.
I don't know what should I do? Please help me, if any one can.

Answer 1

An update:
After installing Java 1.5, the error has become a little more clearer. Instead of the old "no support for encryption type (14)", I now have "KrbException: Invalid argument (400) - Cannot find key of appropriate type to decrypt AP REP - RC4 with HMAC".
However, Ethereal still says des-cbc-md5 is what the AP REP is encoded in (incidentally I got both client and server using des-cbc-md5 over des-cbc-crc). If this is correct, the only conclusion I can come to is that IE or the local system is somehow modifying the HTTP message before it gets decoded by java. Is this even possible or is Ethereal wrong?