How did you fix the problem?
I have the same problem...I've been living with it because it's not a big deal but if there's a simple fix I'll take care of it. I'm using Opera for a browser and I've checked everything mentioned in the previous posts.
Addendum:
Since reading the post about the spell check not being available in Firefox I've tried this site on a couple different browsers. As ATTroll said, the spell check button shows up in IE but not in Opera. IE remembers who I am but Opera and Netscape don't. Now this isn't a complaint because I know their are differences in the browsers that programmers can't address with everything.