MSMQ message format

I've .net application that recieves a string that contains xml according to an exact biztalk schema (i.e. mentions the schema namespace and all the xml). That application in turn puts that message to MSMQ where from biztalk will pick it up.

The problem is .net application, which uses this code:

new Message(xmlStrToSend);

sendQueue = new MessageQueue();

sendQueue.Path = ".\\private$\\" + queueName;

sendQueue.Send(messageToSend); 

Appends its own xml at the beginning and end of the message, like <xml 1.0> <string> </string>, this is due to the default XmlFormatter that it uses for sending objects to MSMQ. But this destroys my message in string, which is built exactly according to the schema and Biztalk gives error, seeing the appended message by .net. I've looked quiet a bit into it but cant find any way of getting rid of this appended xml by .net object to MSMQ, I want the exact string pushed to the MSMQ not any appending. and I am dependent on using the Message object as I need its ID to correlate the response message.

Any help would be very appreciated!!

Regards,

Sajid.