I wouldn't worry too much about it. Athlons are pretty tough. If it really bothers you, do something about it, get a new cooler or improve airflow if case temp is too high.
I will also note that when comparing temps between different machines you can't do direct temp comparisons. My 1800+ has a better version of the same cooler that my friend has, the only difference is that mine has a copper insert in the base. His 2600+ runs cooler. It's just a cool chip. Heck, if it wasn't one of the new locked ones, he could OC it quite a bit. There's no known way to unlock them either, not with a speedstrip or anything else. I don't blame AMD though, if you look at chip prices, they were taking a beating selling 2500+/2600+ chips at sub-$100, only to have them running at 3000+/3200+ speeds.