\"Error Invalid argument. undefined\" on IE, but n


I have a 2 portlets, one included (using portletinclude control) on the other. On Firefox everything works fine (although 2 javascript errors are logged on error console), but on IE 6 and 7 it throws this error:

[POP.012.0002.wm_cafshared/hidden] A client error occured processing the response from the server.
Invalid argument.

I disabled almost all the controls to find out from where the problem is coming from and they stopped when I disabled the form inside the inner portlet.
If I enable the form, although all controls inside it are disabled, the errors come back.
On the server log no errors appear, it looks like some javascript problem but I cannot find and I’m running out of ideas.

As anyone have faced this kind of problem?

You can not use forms in the included portlet, or unless you include portlet outside of the parent portlet form.