Server downtime during hot redeploy of WAR

Hi, I have a setup with Apache and Resin 2.1.12 with a backup jvm and 
persistent sessions using file-store.  I've run this setup on both Sun unix and 
Win XP, with and without Apache and I have encountered the same problem during 
hot redeployments of WAR files:

It seems that when the new WAR file is unpacked, resin still tries to service 
requests and the result is that the user gets a "404 Not Found" error if they 
attempt to access a page at the 'wrong' moment  (I assume because resin has 
deleted the original webapp to make way for the newly redeployed version).  

Is there a way around this so that I can hot-redeploy without any downtime?

Thanks

Dave