Hi,
this patch is the first step to solve #304. It adds some more information into an empty ticket. I think this is as much we can do to make krb5-auth-dialog happy, because krb5-auth-dialog overwrites the client principal found in the ccache with its own data in ka_parse_name(). This data is either just the user name, and the realm is added by the kerberos libraries is default_realm from krb5.conf, or if set the principal set with krb5-auth-dialog-preferences is taken.
For a quick fix there are two possibilites - set the default_realm in krb5.conf or - set the principal with krb5-auth-dialog-preferences
Additionally I'll try to contact the authors of krb5-auth-dialog to see if they agree to try with the principal found in the ccache file if the principal is not explictly and use the user name as a fallback.
bye, Sumit