I have an interface that needs to pass XML to the USPS address service. The XML needs to be passed in the URI like this:

<AddressID="1"><Address1></Address1>">http://SERVERNAME/ShippingAPITest.dllAPI=Verify&XML=<AddressValidateRequest20USERID="xxxxxxx"><AddressID="1"><Address1></Address1><Address2><st1:street w:st="on"><st1:address w:st="on">8WildwoodDrive</st1:address></st1:street></Address2><City>OldLyme</City><State>CT</State><Zip5>06371</Zip5><Zip4></Zip4></Address></AddressValidateRequest>

My problem is appending the XML to the URI. Right now it is passing the XML file to the destination as an XML file not as arguments in the URI. Is it possible to append a string to the end of the URI?

Did you try to use a dynamic port? You can at runtime 'change' or adjust the Address and OutboundTransportType.

An example that might help you: http://biztalk-dev.blogspot.be/2008/02/dynamic-send-ports.html
If you don't want to use orchestrations and want to use a messaging only pattern please check out this link: http://www.digitaldeposit.net/blog/2007/04/can-you-use-dynamic-send-port-without.html