try using the wsdl compiler and compare the generated header file with yours. This will tell you if there is any erronous conversion to C/C++ native types on your part.
Also, look at the outgoing and incoming http packets on your test machine, and look if your SOAP request was valid, and whether it generated a valid response. BTW, any reason you wont use the supplied wsdl header importer? -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
