Ok David,

It works perfectly fine.

Now that you gave me that solution, here comes the next question:

1. In fact that page (web site) has fields that I need to programmaticaly fill with some anwers, and then, after filling all necessary fields, I have simulate a click on a "Send" button in order to send all contents.

For your information, it happens that the web site I'm talking about is for sending mobile phones SMS messages from a local operator, and there is no other way available (I mean, they did not open any other simple way to connect to their server, so I have to use their web site triggered from my application).