[SR-Users] Send/Receive IMs

Hey guys. I am very new to Kamailio. Basically, at this time, I want to generate a SIP message (from an SMS) within Kannel, and send this message to my Kamailio server, which will forward the SIP message to another SIP server. Therefore my Kamailio Sip server would act as a single user agent connecting to only one other SIP server. So what I am unsure of is: 1. Is there a Kamailio interface (such as an HTTP server) which Kannel can connect to in order for Kannel to send multiple messages to my Kamailio Server, which in turn would be forwarded as SIP instant messages to another SIP server? 2. Which Kamailio api can I use to formulate and send the SIP instant messages?  3. Which Kamailio callback function could be called when I receive acknowledgement responses to the SIP IMs I have sent? 4. Which Kamailio callback function could be called when I receive new SIP instant messages sent to me? It would be great if someone could help point me in the right direction. Many thanks. Fred