Thanks to everyone for those suggestions.
I have updated my BIOS time now, and later I am going to trawl through the init scripts to see why this doesn't happen at shutdown.
Somebody suggested that my CMOS battery may be on it's last legs, hence why the BIOS was behind in the first place.
Maybe this is the case,but then if the init scripts (I assume this is where it is done) aren't syncing the Bios time to the system time at shutdown then it is quite probable that the BIOS hasn't had it's time set in over two years.
Regards
Wayne