GWT - Integrate with Payment Gateway - Checkout to Payment Gateway and Handle Redirect

I have a web application developed in GWT. After the person selects what he wants he has to be forwarded to a payment gateway hosted by transecute.com. I need to provide some data such as amount,etc. in the form of fields on a HTML form and then finally submit to a URL that the payment gateway guys have given me. On a JSP page this is simple.. but from GWT I have created a Form Panel and used that to create the fields required and when he clicks on Submit it will post the data out to开发者_StackOverflow社区 the specified URL.

Now on the payment gateway they will redirect the user to a page where he will have to enter his credit card information. Here's my first question: When the Payment Gateway redirect's the user to its page will the GWT module already loaded allow that to happen? Also in the meantime what do I have to do in the onSubmitComplete() event handler?

Now let's assume that the page on the Payment gateway has been displayed and it has redirected the status of the payment to the URL that I specified, in my case its a servlet. After the servlet processes the reply, how do I transfer control back to the GWT module?

Ahh! its very confusing...

Thanks Sethu

OK.. I didnt get an answer from anyone :) Actually what I did eventually was provided a servlet URL to the payment gateway. After the payment gateway finished its job it routed the user back to my servlet. In the servlet I finished the backend processing that I needed to do and send a html page back to the user. This was a look alike to the GWT page that the user was seeing all along. If he clicks on any of the links on the HTML page then the user will land back to the GWT module again.