Determining when an HTTP Post is a SOAP request.

Hello All:

Suppose a component is going to receive an HTTP POST and needs to determine
if the stream of data that it is receiving is an incoming SOAP message.  If
the incoming data is not a SOAP message, it needs to parse the incoming data
as a normal NAME/VALUE sequence.

Does the SOAP spec. provide a mechanism for handling this determination?
Should it?

Thanks,

Brian