REST Client.0 - Error finding field [Authorization] in incoming stream!

Hi,

Do we have case study for invoking REST API. I am trying to invoke a POST request for sending SMS but not able to set the parameters right, even though I tried playing with ‘Headers’ and ‘Parameters’ tabs in ‘REST Client’ plugin. I am not even sure I am doing the right thing, I checked the documentation. Please suggest.

Whatever I do I get the following error : REST Client.0 - Error finding field [Authorization] in incoming stream!