The application relates to a method for setting up a call from a non-IMS telecommunication network, comprising a Network Gateway Node (NGN), to a destination node in an IMS network. The method comprises the NGN interfaces a combined database node comprising a Home Location Register (HLR) and a Home Subscriber Server (HSS). The method further comprises routing the call to the destination node in the IMS network, of which address is determined by information received from the combined database node. The method further comprises sending, sending, in response to receiving an initial call setup request message, an information request message to the combined database node for obtaining routing information for the setup of the call, the information request message comprising an indicator indicating at least one type of response that the NGN is able to process.