Its not an uncommon request (in fact I got one in email today) to want to receive:
1. Non-XML data in a receive-port
2. XML messages of differing XML schemas within a single receive port
So how do you do that with BizTalk Server?
1. Set the messagetype property on your receive port to System.xml.xmldocument (yes I know in case 1 you are receiving non-XML data, but do it anyways)
2. Set-up a filter on the receive shape in orchestration which will pickup the message. Make sure you set your filter appropriately so you don't pick-up all documents.
To access the data as a stream (if you want) then you can use this in an expression shape:
XLANGPart.RetrieveAs( typeof(Stream) )
Credits to Yossi