I am using pump-0.7.0-1. Here is the problem I have: When the expiration time is achieved for a DHCP connection the command "pump -r -i eth1" is blocked! Consequently the shutdown program is blocked (pump is used in /etc/sysconfig/network-scripts/ifdown which is called by /etc/rc.d/init.d/network). Temporary solution: I've replaced "pump -r -i eth1" by "skill pump"
Fixed in new pump available w/ piglet