Manipulating the soap header from bpel

[Jim Alateras]

Is there anyway to manipulate the SOAP header using the <copy> construct 
in BPEL. The specific example is that I need to make a request to a 
service to retrieve a 'session token' and in subsequent calls to the 
service I need to embed the 'session token' into the soap header.

cheers
</jima>