hope me metachat - thunderbird refuses to load my inbox file. anyone know anything about Thunderbird refusing to load inbox files?→[More:]

I channel around 6 email accounts through thunderbird (v 1.5.0.5), and one (my work one, natch) is misbehaving. I start thunderbird, and the inbox for my work email does not appear (it is meant to contain a couple of thousand messages - I know, I know). Going into the relevant profile folder, I see that the inbox file still exists and is of the right size (I'd heard of bugs, perhaps virus-related, that might have deleted the inbox file), but thunderbird just refuses to load it. All the messages that have been filtered out of the inbox are still there in their respective folders.

Eventually, presumably due to some kind of memory leak (my knowledge and savvy runs out at this point), my pc seizes up if I leave thunderbird open. So I am reduced to using webmail for both the accounts I use daily.

any ideas?