What ISP are you using? The reason I ask is that some consumer broadband ISP's (including mine, AT&T) have begun filtering the webserver port in an attempt to contain the codered virus. Everything still works great on my internal network and I can still connect to the box externally on other ports, but I can no longer access webpages externally because the port is now blocked. This change has only occurred in the last week or so for most ISP's.
Hope this helps,
John G.