I reckon it should be more than happy to do that. It's got the QX9770 in its CPU compatibility list, which is a 400 FSB CPU, so it should go without a hitch. There will likely be less options for overclocking, but it shouldn't really handicap you as you have a good solid CPU that won't need much coaxing to get that clock out of it.
Mosfet heat shouldn't be a problem either, especially with such a modest Vcore. If you are a little worried though, there are after market mini individual sinks you can buy. Ldsmeasap linked to some in a post that recently got resurected, and they look impressively solid, and are made of copper.
Enzotech MOS-C1 Forged Copper Mosfet Heatsinks - Multi-Pack (10 pcs)
You're going to enjoy tinkering with this CPU, I guarantee it. A 4GHz quad means no more compromise between more cores and more MHz. A Q9550/Q9650 would be my weapon of choice if I had the money, second only to a complete i7 D0 stepping overhaul.