This is your resource to discuss support topics with your peers, and learn from each other.
Pleaser check http://supportforums.blackberry.com/t5/Cascades-Development/Sending-data-via-HTTP-post/td-p/2006789
and first https://developer.blackberry.com/cascades/documentation/device_comm/networking/index.html
The httptest sample app demonstrates how to post a message to a server. Checkout this sample on Github.