The present invention relates to a method for treating an inflammatory bowel disease, including administering an effective amount of 1,4-dihydroxy-2-naphthoic acid or a salt thereof. When the SIP converter 10 detects coded DTMF information from one of the NWs while a session is established between the SIP terminal 41A and the SIP terminal 41B, the SIP converter 10 determines whether the other of the NWs supports the coded DTMF information. Mobility is provided to the user and hardware portability is provided by establishing a user desktop interface responsive to a login request which presents to the user a desktop screen through a web browser interface which accesses and downloads selected application programs from the server responsive to a request from the user on the user desktop screen at the client. The signalling message is transmitted from the transmitting telecommunciation device to the receiving telecomunication device.