Vars to swf from browser

Im trying to pass a huge string (12k) to my flash from the browser using the param embed tags.

HTML e.g.
<param name=“movie” value="/pix/inzalo/menutest/080105v28_slim_Menu.swf?menuData=data_data_data_data…

AS e.g.

tmp = _root.menuData;

The flash recieves the data just fine if its not so large. I know that flash can accept vars that are up to 64k big.

My flash does have a preloader for the swf but I think that I need some kind of LoarVars preloader for it? (oddly enough if I half the data size of the var’s being passed in to the flash then it render’s just fine in FF but does nothing in IE?)

Can any one give ANY advice please?