How to pass dynamic created forms to a Javascript function in Netscape ?

Hi !
I have following problems:
I have written a Javascript that produces different forms depending on the option selected in a pulldown menu (also javascript).

The created forms have always the same name, but it differs in the number of inputs.

Now i have a button with an onclick-attributem which loads a Javascript function with the dynamic form as an attribute.

Now the problem is following:
In IE it works perfectly, the form is passed in the right way to the javascriptfunction, but it doesn't work in Netscape. In NS isn't passed anything. It is passed with document."formname" to the function.

What is the problem in Netscape ? How can it be solved ? Please need help.