recovery lag question

Hi, I've set up a warm standby box with postgresql 8.3.8 and pg_standby.
Everything seems to be ok except and the wal files are being copied
across and being processed during the recovery as you'd expect but I
have one question. The recovery seems to be processing the final wal
files (about 30) at the same rate as they are generated, which is
approximately every 6 minutes. This means that it is currently lagging
behind the primary by about 3 hours. I assumed that the recovery would
process the wal files as fast as possible until it caught up and then
waited, there appears to be no load on the secondary server so I'm
guessing it is sat waiting but i may be wrong.

Thanks

John