Does Fred Thompson want my money?

I was excited about Fred Thompson for a while, before he actually got in the race, because I liked his blog posts -- both their content (usually) and their style. I was not thrilled with the style of his campaign -- recycled politician-pap for the most part -- but I am still inclined to prefer him over the other major candidates, so I decided to pony up a bit of money. I tried to contribute $15.00 -- the same amount I've recently sent to ACLU Indiana and to St. Jude's -- to his campaign. However, when I entered that amount at the Donate link on his campaign website, I got a little message in red saying the amount was "inappropriate".

And how inappropriate is it to diss a would-be contributor? (Is that how to spell "diss"?)

I've sent an email, also through the website, asking whether they really don't want my money. I'll update with any response I get.