WebService Action Block - Trace

Hi All,

I am using webservice action block in a transaction. And i want to capture the error if this action fails. I will check the success parameter and if it is false then i want the detailed error. I checked the Trace parameter of the Webservice Action, but to my surprise it is also returning the boolean value. For example, if i provide the username and password wrong, it will give unauthorized error. This info i want to pass as output of my transaction.

regards,

Gowtham