settimeofday within jail

[Colin Percival]

   Ok, this is a wierd question: How hard would it be to allow jails to 
have local clocks which could be manipulated within those jails?

   The reason I'm asking is this: As those of you who attended my BSDCon 
talk will know, FreeBSD Update plays games with the clock (specifically, it 
sets the clock forward by 400 days) in order to locate timestamps embedded 
in binary files.  I'd like to put as much as possible into a jail, to 
protect my buildbox against the unlikely possibility that some malware gets 
into the FreeBSD CVS repository.
   If jailed clocks would be too difficult, I can certainly work around it; 
but since I have almost no knowledge of kernel internals I thought I'd ask.

Colin Percival