Exit kcmbind, remove your $HOME/.kde/share/config/kcmbindrc file. Start kcmbind and you will get the setup dialog. Choose the options you want but leave the "Parse status" button unchecked. Save and exit.
Go to the setup dialog, Press the checkbutton for "Auto Reverse Lookup", save and exit the dialog. Restart kcmbind and you will notice that the reverse domain has disapeared. Easy now, It will be automaticly updated.