Hi,
For your purpose you can use the application integrator Generic iView (it's one of the AI templates)
You can modify the POST & GET using the "RequestMethod" parameter.
For more details:
http://help.sap.com/saphelp_nw70/helpdata/en/36/5e3842134bad04e10000000a1550b0/frameset.htm
Best regards,
Etay