SIP REGISTER denied and sip unregister peer

Hello, i downloaded the latest version of ASTERISK() 1.2.6 … i work with it … and this week i work to implement the features of DENY a SIP REGISTER MESSAGE based on the peer name (already supports for name-matching, like the patterns in the extensions.conf) and a CLI and MANNAGER commands for unregister sip peer … does somebody know how can i submit this code and maybe be part of the official source code of the ASTERISK() version ??? … the code its implemented in the source file chan_sip.c