[Serusers] Need a way to delete a URI parameter if present from the INVITE

A given system is sending me INVITEs of the form: INVITE sip:6663338888@111.222.33.44;cic=9876;rn=6663331212;npdi SIP/2.0 that includes some URI parameters, eg the things after the semi-colon. In this case, the cic=nnnn value is really some internal routing number and not a real PSTN CIC value (like 0288 for AT&T). So when this eventually reaches a switch on the PSTN, that switch sees that someone has already determined the CIC and it attempts to route using what really isn't a CIC at all. I would like to strip this "cic=nnnn" out of the call within SER, and while there are a number of documented rewriteuri functions for altering the URI in SER, there doesn't seem to be anything that can be used to get at URI parameters. For the above, I would like to trim it to: INVITE sip:6663338888@111.222.33.44;rn=6663331212;npdi SIP/2.0 as the rn= and npdi values are sane and can be used by the destination switch. Is there such a beast, or is the only options to add a function/module or use the exec to invoke an external program to do the job? Thanks in advance.