I'm not sure if this is a firefox glitch or a drupal glitch but regardless maybe someone can help me.

When I create a new page in drupal using firefox and select the php input format and type the following.

preg_match($test1,$test2,$test3);

Then click preview that last code shows up in the text box but is quickly replaced with.

($test1,$test2,$test3);

If I view the page source and look at the text box code preg_match is there but if I click preview again the text box is submitted as if preg_match was never there.

Now if I repeat those steps in IE then the glitch never occurs.

Can anyone help me fix this issue? it's quite a pain in the rear.