[bairy]

I get the same error in IE7. I'm gonna see if I can work it out.

Edit: Had a quick look. It seems that this line:
h_spellform.spell_formname.value = formName;

confuses IE. It works in Firefox but IE7 doesn't recognise "spell_formname" as part of the form object.

I'm afraid someone with more knowledge of javascript OO will have to have a look.

Also Replicators I found a bug, don't know if it's just my board. Within a thread if you click edit on any of the posts then the spell check button, it will check the text in the quickreply at the bottom. I'm guessing there's a mix up over the id of the textarea it should be reading.