[Serusers] SIP Torture Tests Using Sip Foundry SFTF

Hi All. I'm doing some validation checks against my SIP proxy (ser-0.9.1) using SFTF http://www.sipfoundry.org/sftf/ I'm seeing that some tests are making further through my ser.cfg than I'd like. For example, SFTF test case214 sends an INVITE message to SER with an invalid Content-Type header. SER replies with a 404 User Not Found, which is technically correct, since the the destination doesn't exist, but SFTF complains that SER should have returned a 415 Unsupported Media Type error instead. So my question is this; even though ser rejected the SIP message, shouldn't it have performed some checks on the message to validate things like Content-Type, R-URI, etc to make sure the message is not corrupt or invalid? If not, does it make sense to do so before letting a SIP message get too far in to my ser.cfg? I did find this article in the archives which seems to indicate that ser should [happliy] ignore things it doesn't understand - but is this safe? http://lists.iptel.org/pipermail/serusers/2004-November/013171.html Regards, Paul