>>the invocation of method TrazerEdicoes(), returns a XML string. Why I must call .ToString()??
>I don't think you have to, but I think it optimizes the code to perform better. Just a guess, I should findn out.

hmmm... I found, Mike... I´ve had declared my method such as:

Procedure TrazerEdicoes() as XMLString

I´ve put "XMLString" in order to know that that comes a XML string from that method... doing that way, I need to use .ToString() on the method call... changing the declaration of the method to

Procedure TrazerEdicoes() as String

it works without the ToString()... obviously, C# doesn´t know anything about a "XMLString" data type. :)