Personally I haven''t seen any mod that does that. But have a look for yourself at the RM. If there is no such mod then you can put in a request at the Request forum and hopefully someone will code it for you.
They don't look like they do unfortunately. Does anyone else have any more suggestions? I would have thought it was a very common thing that admins wanted to log forum access. It seems odd that a site could be under attack but there is no way to even be aware of this.