Dear all, David is right. Get is limited to 256 chars (?) and not that nice. The prototype popup window is named a frame in Firefox. So it must be possible to be accessed normally? Sorry folks I am not that firm in js. But I am shure there is an option. The "normal" window.open has no effects like prototype. There are several other scripts, which are already using prototype. Till now it was OK to support just an id. But the values put in the form must be possible to use. e.g. name: textfield: Peter Rover subject: spring time text: blah, blah..... With onclick I opened the prototype window and wanted the values (peter Rover, spring time, and blah) within the prototype window.