Method for activating a connection in a communications system, mobile station, network element and packet filter

The invention relates to a method for activating a user data transfer connection ( 11 ) between a mobile station ( 1 ) and a node ( 2 ) of a communications system. For some of the connections ( 11 ) the mobile station ( 1 ) sends packet filter values ( 16 ) to said node ( 2 ), the node ( 2 ) assigning downlink packets ( 6 ) received to a connection ( 11 ) of which the filter values ( 16 ) match with values included in said packet ( 6 ). In order to enable an activation of a connection while at least some filter values required for the connection are not yet available, it is proposed that in such a case, when activating a new connection, the mobile station ( 1 ) sends for said connection ( 11 ) at least one filter value ( 16 ) to said node ( 2 ) that does not match with the corresponding value of any possible packet ( 6 ). Alternatively, the mobile station ( 1 ) transmits a parameter ( 17 ) to the node ( 2 ) indicating whether the new connection is allowed to be used.