Method for withdrawing from a Session Initiation Protocol, SIP, session set-up loop, that is to be established, by a SIP-Invite receiving node in a communication network, while passing on information available at said node to other nodes and applications on other nodes further on in said loop to be established, comprising the steps of; • Receiving by said node a SIP Invite message from a SIP Invite message sending node, • Halting SIP session set-up, • Comparing said SIP Invite message with conditions stored at said SIP Invite message receiving node and to be applied to SIP Invite messages, • Continuing set-up of the SIP session without removing itself from the SIP session set-up loop when said SIP Invite message does not meet said conditions, • When said SIP Invite message does meet said conditions; - Forwarding fields of said SIP Invite message to higher level functions in said SIP Invite message receiving node, - Receiving a command in return either to continue the SIP session set-up without removing itself from the SIP session set-up loop or to redirect, in which the command includes SIP Invite header field identifications with field content values, and subsequently; ■ Assembling a SIP Redirect message and include the SIP Invite header field identifications with field content values in header URI parameters of said SIP Redirect message, ■ Sending the SIP Redirect message back to a SIP Invite message sending node and discontinue SIP session set-up. • Receiving by said node a SIP Invite message from a SIP Invite message sending node, • Halting SIP session set-up, • Comparing said SIP Invite message with conditions stored at said SIP Invite message receiving node and to be applied to SIP Invite messages, • Continuing set-up of the SIP session without removing itself from the SIP session set-up loop when said SIP Invite message does not meet said conditions, • When said SIP Invite message does meet said conditions; - Forwarding fields of said SIP Invite message to higher level functions in said SIP Invite message receiving node, - Receiving a command in return either to continue the SIP session set-up without removing itself from the SIP session set-up loop or to redirect, in which the command includes SIP Invite header field identifications with field content values, and subsequently; ■ Assembling a SIP Redirect message and include the SIP Invite header field identifications with field content values in header URI parameters of said SIP Redirect message, ■ Sending the SIP Redirect message back to a SIP Invite message sending node and discontinue SIP session set-up. - Forwarding fields of said SIP Invite message to higher level functions in said SIP Invite message receiving node, - Receiving a command in return either to continue the SIP session set-up without removing itself from the SIP session set-up loop or to redirect, in which the command includes SIP Invite header field identifications with field content values, and subsequently; ■ Assembling a SIP Redirect message and include the SIP Invite header field identifications with field content values in header URI parameters of said SIP Redirect message, ■ Sending the SIP Redirect message back to a SIP Invite message sending node and discontinue SIP session set-up. ■ Assembling a SIP Redirect message and include the SIP Invite header field identifications with field content values in header URI parameters of said SIP Redirect message, ■ Sending the SIP Redirect message back to a SIP Invite message sending node and discontinue SIP session set-up.