The invention relates to a method for performing a capability discovery. The method is implemented by a home server (10) and comprising the steps of:—receiving (101), from a user terminal (11), a principal discovery request (12) comprising a complete contact list,—from the complete contact list, determining (102) which contacts are locally known, and which contacts are locally unknown,—generating a limited contact list containing all contacts that are locally unknown,—sending (103) a plurality of secondary discovery requests (19) comprising the limited contact list to a plurality of remote servers (17, 18),—receiving (104), from each remote server (17, 18), a notification (16) containing information about contacts contained in the limited contact list,—sending (105), for each unknown contact by the home server (10) and the plurality of remote servers (17, 18), a back-end subscription to a home IMS core (21).