$$Return not working in IE8?

I have a small app that uses the $$Return field. It has always worked fine (about 10 yrs now) but with IE8 the $$Return field is not recognized and IE8 throws an error. The field does not show up in the HTML source. It does show if I only change the name to Return. (of course it doesn’t work with that name.)Has anyone else seen this issue with IE8?

Subject: What is the error?

What is your $$return formula?