Tool : Nokia WAP Toolkit 1.3b with Nokia user agent.
In my wap application, I got the problem where the url is too big. To get around this, I use the method="post" attribute in the "go" element. The user is then able to select the link (i.e. anchor) and execute the "go" command which call another file.
But, if I allow the user to go back (with prev element) to the previous file, none of the data that have been posted with method="post" stay posted. I'm developping an ASP application and I need to put some data from the user agent to the server. That's why I can't always use WML variables.
Is it possible that the browser is caching? If it is, and you go back and then try to POST to the same URL, it may not actually do a POST.
If caching isn't the problem, you might want to try changing the original page to set a variable in a setvar inside a pair of onevents (forward and backward), and then set the postfield using the variable.