Adding custom button in KAddressBook

Hello list,

  I hope this is the correct place to ask.  I am syncing my address book 
with a server using a custom rsync script.  It would be very useful if I 
could do this using a button in the gui of KAddressBook that just runs the 
script.  Is there a way to implement this?  Going quickly through the 
KAdressBook hand book I did not find anything. 

Thanks,
Giorgos