[Sip-implementors] message-body questions

[John Fisher]

Hello,   I am newbie to SIP.  I have a question regarding the "message-body" of a SIP request.  I have seen some call-flow examples with multiple "message-body"s along with their respective "entity-header"s, but I have seen no mention of this in RFC2543.   Is this allowed?  Also, is there is list of valid "content-type"s to describe the different bodies?  (ie application/sdp).   Thanks in advance