KMobiletools Phonebook only from phone, not from SIM

Hi!
I am having a little problem with my Sony K750i which is that i see my contacts doubled in my KMobiletools addressbook, one from SIM and one from the phone. I don't consider deleting one of them because
a) my SIM is full, i can't save any more contacts there, so i need the phone memory for new contacts
b) in case my phone stops working i at least have my SIM Contacts left so i need the SIM-Backup
So how can i make KMobiletools ignore the contacts from the SIM and only show those from the phone?

Thanks in advance and even more thanks for this great program :)