dhclient problems

[<erik@ehanson.net>]

Hello,
  My cable modem provider just changed their dhcp system
and I am now having trouble resolving an address with
dhclient in OpenBSD 3.0 and 3.1.  Other dhcp clients in
other operationg systems, such as windows and linux, are
able to resolve addresses but dhclient in OpenBSD can not.
 When it does try to get an address i see an error once in
a while that reads:

DHCPACK offer from <ip of dhcp server> rejected due to
bogus yiaddr of 0.0.0.0

Has anyone experienced anything like this before or have
any idea what might be going on?

I have called my ISP and they are clueless when it comes to
OSes other than Windows.  Everythig was working fine under
OpenBSD 3.0 before they made this change.

Thanks.
-Erik