Method for improved handling of IP multimedia subsystem calls and configuration of a user equipment in the situation that the user equipment is able to attempt an IP multimedia subsystem emergency call or an IP multimedia subsystem call, and the user equipment being connected to a visited mobile communication network via a radio access network of or associated with the visited mobile communication network, wherein the method comprises the following steps: -- in a first step, an IP multimedia subsystem call parameter information or an IP multimedia subsystem emergency call parameter information is transmitted by the visited mobile communication network to the user equipment, -- in a second step, during or subsequent to the first step, the user equipment - upon attempting an IP multimedia subsystem emergency call or an IP multimedia subsystem call - applies or acts according to the content of the IP multimedia subsystem call parameter information and/or of the IP multimedia subsystem emergency call parameter information, wherein the method is characterized by comprising a third step, prior to the first step, wherein during the third step, the user equipment roams to the visited mobile communication network with IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters being stored in the user equipment according to previously stored values of these IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters, wherein the IP multimedia subsystem call parameter information and/or the IP multimedia subsystem emergency call parameter information received in the first step comprises parameter information that are adjusted to the visited mobile communication network to which the user equipment is attached, such parameter information being stored and applied - at least during a certain validity time interval - rather than IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters being stored in the user equipment according to previously stored values of these IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters. -- in a first step, an IP multimedia subsystem call parameter information or an IP multimedia subsystem emergency call parameter information is transmitted by the visited mobile communication network to the user equipment, -- in a second step, during or subsequent to the first step, the user equipment - upon attempting an IP multimedia subsystem emergency call or an IP multimedia subsystem call - applies or acts according to the content of the IP multimedia subsystem call parameter information and/or of the IP multimedia subsystem emergency call parameter information, wherein the method is characterized by comprising a third step, prior to the first step, wherein during the third step, the user equipment roams to the visited mobile communication network with IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters being stored in the user equipment according to previously stored values of these IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters, wherein the IP multimedia subsystem call parameter information and/or the IP multimedia subsystem emergency call parameter information received in the first step comprises parameter information that are adjusted to the visited mobile communication network to which the user equipment is attached, such parameter information being stored and applied - at least during a certain validity time interval - rather than IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters being stored in the user equipment according to previously stored values of these IP multimedia subsystem call related parameters or IP multimedia subsystem emergency call related parameters.