DHCP and the firewall

[Craig Emery <fedora-test cemery org uk>]

Are there any issues with using DHCP and the firewall?
Do I have to allow traffic of a certain kind in?
Do I have to make this change using system-config-security?

I've got the firewall enabled, but when I try and raise the appropriate 
interface, I get a timeout. I'm just wondering if the DHCP reply is 
being filtered.

On a side: Is there a log that'll let me know that the packets were 
being dropped?
Where are the docs on how the firewall is configured?

TIA

Craig.