Processing Instructions and MSMQ

Hi all.  This one has me stumped and was hoping i could get some insight here.

I need to add processing instructions to the xml outbound from my orchestration.  Which i accomplised by adding this to my message assignment shape.

xOut(XMLNORM.ProcessingInstructionOption) = 1;
xOut(XMLNORM.ProcessingInstruction) = “some instructions”;

When I pass my out document out a FILE adapter send port it works just fine (pipeline = XmlTransmit).  When I pass it out a WCF-MSMQ adapter send port, the processsing instructions get dropped. 

When i say dropped, i mean that they aren’t available to the process that picks up messages from the MSMQ (which is a another BT orchestration with XmlReceive pipeline).  I have turned the receiving process off and examined the messages while they are still in the queue and there are no processing instructions in the message.

Any thoughts on what I might be missing?  I found an old post from Stephen where he talks about “Processing Instructions being demoted into the message inside the pipeline”.  What does that mean exactly?

http://www.ureader.com/msg/12071009.aspx