Adapted sip_subscribe_winfo.py to new Subscription class

darcs-hash:20090525174001-58103-cb6c2cb89a3fff84a056598f8777206297160dbf
Adapted sip_subscribe_xcap_diff.py to new Subscription class

darcs-hash:20090525174027-58103-10468582233dfe3fab02e8e69012d782e86f4992