RH 8.0 vs. RH7.3 driver issues

[Harlan Jillson]

hi all,
  I just subscribed to the list, and am looking for some suggestions.
  I have a device driver for a RS485 card that does microlan
communications between several devices.  The driver was written a couple
of years ago using the 2.2 kernel in RH 6.1.  It's was updated for 2.4
kernel when RH7.3 was released and has been working fine.  RH8.0 is
apparently a different story, as there appears to be problems with
scheduled timeouts (polling intervals) and maybe some interrupt issues.
My question is are there any known problems ( RH kernel 2.4.18-3)?  I
know I'm dealing the revamps in the scheduler and timer areas and then
there's the shift from gcc 2.96 to 3.2.  
Thanks for any suggestions,
Harlan