the preferred embodiment will now be described on the basis of a mobile terminal connected to a cellular network such as a 3rd generation mobile communication network comprising a circuit - switched core network and a packet - switched core network . in the context of the present invention , a service is understood to be any entity that can provide information , perform an action , or control a resource on behalf of another entity . a service may be implemented as software , hardware , or a combination of hardware and software . furthermore , the term proxy is used to indicate any mechanism whereby one system “ fronts for ” another system in responding to protocol requests . proxy systems or servers are used in network management to avoid having to implement full protocol stacks in simple devices , such as modems . [ 0032 ] fig1 shows a schematic diagram of an initialization , storing and changing procedure of a trigger control information . the operator of a network 30 may define available or used service configuration triggers and may provide them as a trigger control information to a first terminal equipment or mobile terminal 11 and a second terminal equipment or mobile terminal 21 . these mobile terminals 11 , 12 comprise a usim ( universal mobile telecommunications system subscriber identity module ) or volatile memory 12 , 22 , e . g . an eeprom ( electrically erasable programmable read - only - memory ), in which the trigger control information can be stored . the trigger control information defines events and / or conditions , which shall trigger a server address discovery procedure or any other procedure for obtaining configuration parameters of servers or other data sources , to be executed . the server addresses can be addresses of a www ( world wide web ) proxy , a wap ( wireless application protocol ) gateway , a wap push server , a proxy voip ( voice over ip ) and multimedia cscf server , a localized service area specific server , a defined geographical area specific server etc . when a triggering event or condition comes true , e . g . is detected by the first mobile terminal 11 and / or the second mobile terminal 21 , a configuration or reconfiguration procedure is started to get new server addresses or other configuration parameters from the network 30 to be used by the terminal . a control information can be initialized , changed and stored in the following ways , depending on the operator and user needs and an agreement between them : in step 1 , the operator of the network 30 can initialize the trigger control information and store it in the usims 12 , 22 of the first and second mobile terminals 11 , 21 when the usim card is sold to the customer . then , it can be updated later e . g . by using a sim application tool kit or other similar solutions . as an alternative , the trigger control information can be stored in the volatile memory ( e . g . eeprom ) or ram ( the first and second terminals 11 , 21 ). in any case , the operator can allow a user to change the trigger control information and / or the operator can also change it using the mechanisms described in step 3 and / or step 4 . in step 2 , the changed trigger control information is then stored in the usims or eeprom 12 , 22 or the ram of the first and second mobile terminals 11 , 21 . as indicated by step 3 , the operator may broadcast changes in the trigger control information as a part of a system information message . this is a particularly applicable when the trigger control information of a plurality of mobile terminals registered to the network 30 is to be controlled . as an alternative or in addition thereto , step 4 indicates a provision of the trigger control information to a second mobile terminal 21 in a dedicated manner , when the second mobile terminal 21 registers to the network 30 . this may be achieved e . g . during the delivery of server addresses to the second mobile terminal 21 according to a user profile or as a part of it using any signalling protocol , such as dhcp , sm ( session / service management ), slp or sip for example . thus , the first and second mobile terminals 11 , 21 are continuously provided with an updated trigger control information adapted to their current location . the address or other configuration parameter discovery procedure may be performed as follows . when the mobile terminal detects or determines a trigger event or trigger condition as defined by the stored trigger control information , it may send a slp query in order to obtain an ip address of a www proxy or some other required proxy server . also dhcp query may be triggered in order to obtain an ip address of a respective cscf or some other service lookup server . for example , when a ps mobile terminal enters a ( new ) cs network , the queried dhcp server answers with a p - cscf address . the mobile terminal may then contact the p - cscf in order to get a list of available multimedia services . the p - cscf can take into account the type of network where it is connected , so that not all , of the services designated for the ps domain may technically be possible in the cs domain , e . g . due to the low capacity of the cs network . the p - cscf answers with a corresponding list of services , such that the user of the mobile terminal is now provided with a list of services available in the network . it is noted that the any of the initially described discovery procedures , e . g . according to the dhcp or dns protocol or slp protocol , or other discovery protocols may be used for obtaining the required address or other configuration parameters . [ 0040 ] fig2 shows a signaling diagram of a service configuration procedure between the first mobile terminal 11 and the network 30 . in step 1 , the trigger control information is provided for the mobile terminal 11 by the network . this control information is then interpreted in step 2 by the mobile terminal 11 , and the defined service configuration triggers are then stored in the volatile memory and / or the usim 21 of the mobile terminal 11 . in step 3 , a triggering event happens or location conditions come true , as defined by the trigger control information , and a service configuration or reconfiguration procedure is started by the mobile terminal 11 . thus , the mobile terminal 11 issues a service configuration request in step 4 so as to ask for new server addresses or other configuration parameters from the network 30 . in step 5 , the new server addresses or other configuration parameters are delivered to the mobile terminal 11 by a service configuration response message . the operator of the network 30 may select the most suitable triggers for service configuration or reconfiguration based on his own needs , i . e . service configuration customization , and may define them in the referred trigger control information . as an example , the following events or conditions can be defined as triggers : 2 . a routing area update where a new routing area of a ps domain is entered , 3 . a location area update where a new location area of a cs domain is entered , 4 . a change in the ip network point of attachment , e . g . change of ggsn ( gateway general packet radio services support node ) or ha ( home agent ), 5 . a change of a localized service area ( lsa ), which is an operator - defined area , for which specific access conditions apply and which may correspond to an area in which the core network offers specific services , 7 . a change of the location of all mobiles in geographical area ( lamga ), 8 . a roaming from a first plmn to a second plmn , by which also the operator is changed , and 9 . a movement outside a predefined geographical area , which may include position definition functions , e . g . global positioning system ( gps ) etc ., in the mobile terminal 11 or the network 30 . of course other suitable trigger events and / or conditions associated with a terminal movement or change of location can be defined . [ 0052 ] fig3 shows a schematic block diagram of the mobile terminal 11 . it is noted that only those functions relevant for the present invention are shown in fig3 . the mobile terminal 11 comprises a transceiver ( trx ) 113 for transmitting and receiving rf signals to / from the network 30 . the trx 113 is controlled by a signaling control unit 112 which is arranged to generate and interpret signaling messages transmitted to and received from the network 30 , respectively . the signaling control unit 112 is controlled by a trigger unit 111 based on the trigger control information received from the network 30 . an initial configuration or setting of the trigger events and / or conditions may be obtained when a sim or usim card 101 is inserted into a usim or sim unit 110 . the trigger control information of the sim / usim card 101 may then be interpreted in the usim or sim unit 110 , and the corresponding trigger events and / or conditions may be supplied to the trigger unit 111 . based on a corresponding signaling of the signaling control unit 112 , which indicates the receipt or detection of messages or other events and conditions , e . g . the triggers indicated above , the trigger unit 111 may then decide whether to initiate a discovery procedure for obtaining the required configuration parameters , e . g . server addresses of a server or proxy server . furthermore , the signaling control unit is arranged to perform or initiate an update procedure when the trigger control information is received from the network 30 together with a broadcast signaling message or a response message to a network registration procedure . it is to be noted that the units or blocks 110 to 112 may be implemented as concrete hardware circuits or as software routines of a corresponding control processor arranged in the mobile terminal 11 . the network operator may also define multiple triggers to be used . an example of such a case is shown in fig4 . fig4 shows a moving route of a mobile terminal through a network configuration comprising a first network plmn - a and a second network plmn - b . both networks comprise location areas la , routing areas ra and individual cells . some of the individual cells are combined to a localized service area solsa with a specific lsa identity . furthermore , a defined geographical area ( dega ) with a predetermined dega identity and a location of all mobiles in geographical area ( lamga ) with a predetermined lamga identity are provided . when the mobile terminal moves according to a route indicated by the arrow in fig4 service reconfiguration procedures may be activated several times at predetermined locations indicated on the arrow . at a first location p 1 , a location area update is signaled by the signaling control unit 112 . then , at a location p 2 , a routing area update is signaled . moreover , at the location p 3 , a dega change is signaled , and at the location p 4 an lsa change is signaled . when the mobile terminal enters the second network plmn - b , an operator change is detected due to the roaming from the first network plmn - a to the second plmn - b . this may include a deregistration from the operator of the first network plmn - a and a registration to the operator of the second network plmn - b . this may be accompanied by an initial service configuration . at the location p 6 , a lamga change is detected , and a cell update is signaled at the location p 7 . finally , an additional lsa change is detected at the location p 8 . based on the trigger control information and the corresponding registered trigger events and / or conditions , a service configuration or reconfiguration procedure may be activated at predetermined ones or each of the above locations p 1 to p 8 . it is noted that some of the above changes , updates may also trigger a change in the service provider . this is the case , when the network operator has rent a service area from one company and the other service area from another company . thus , the service configuration procedure according to the present invention also enables a user - friendly management of services in future mobile internet systems as specified e . g . in the 3gpp ( 3rd generation partnership project ) standard specifications . it is noted that the present application is not restricted to the above preferred embodiment , but can be applied in any network architecture , where service configuration parameters have to be downloaded or transmitted from the network to a terminal device . furthermore , any desired trigger event and / or condition can be used for activating the discovery procedure . the preferred embodiment may thus vary within the scope of the attached claims .