Description of problem:

Rebooted after installing today's updates-testing updates including NetworkManager-0.8.0-11.git20100503.fc13.i686, dhclient-4.1.1-21.fc13.i686, kernel-PAE-2.6.33.3-72.fc13 and now my network will no longer come up.   Log from attempt to connect:

May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) starting connection 'Auto eth1'
May  4 08:37:41 orca NetworkManager: <info> (eth1): device state change: 3 -> 4 (reason 0)
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 1 of 5 (Device Prepare) scheduled...
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 1 of 5 (Device Prepare) started...
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 2 of 5 (Device Configure) scheduled...
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 1 of 5 (Device Prepare) complete.
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 2 of 5 (Device Configure) starting...
May  4 08:37:41 orca NetworkManager: <info> (eth1): device state change: 4 -> 5 (reason 0)
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 2 of 5 (Device Configure) successful.
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 3 of 5 (IP Configure Start) scheduled.
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 2 of 5 (Device Configure) complete.
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 3 of 5 (IP Configure Start) started...
May  4 08:37:41 orca NetworkManager: <info> (eth1): device state change: 5 -> 7 (reason 0)
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Beginning DHCPv4 transaction (timeout in 45 seconds)
May  4 08:37:41 orca NetworkManager: <info> dhclient started with pid 2421
May  4 08:37:41 orca NetworkManager: <info> (eth1): device state change: 7 -> 9 (reason 0)
May  4 08:37:41 orca NetworkManager: <info> Marking connection 'Auto eth1' invalid.
May  4 08:37:41 orca NetworkManager: <warn> Activation (eth1) failed.
May  4 08:37:41 orca NetworkManager: <info> Activation (eth1) Stage 3 of 5 (IP Configure Start) complete.
May  4 08:37:41 orca NetworkManager: <info> (eth1): device state change: 9 -> 3 (reason 0)
May  4 08:37:41 orca NetworkManager: <info> (eth1): deactivating device (reason: 0).
May  4 08:37:41 orca NetworkManager: <info> (eth1): canceled DHCP transaction, DHCP client pid 2421

This connection is a Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet card that I added to the machine.  There was no ifcfg-eth1 for it and was working fine for a couple days.

I created an ifcfg-eth1 and used ifup eth1 to bring up the network.  With ifcfg-eth1 present, NM is able to activate the network.

Downgraded dhclient but same behavior.

Downgraded NM and it is now able to activate "Auto eth1" automatically again.