Thanks Adam for your answer.

 

The problem is that it actually strips under 6.0. And as I said it did not before !

 

I have for sure tried to upgrade to 6.1, but then I get a compilation error and can't make it work (I have all the new Dlls and client files and get an error in the Dialogs folder during compilation).

 

Regarding 6.0 and the new issue, I have not modified a single line of code, but I have changed my development environment.

 

New computer, from XP Pro to Vista Pro, and added ASP.Net AJAX : could it be the reason of my problems ? Do I have to change anything in the web.config for example ?

 

Thanks.