FC5. Problem activating eth1 instead of eth0.

[Nat Gross]

Hi.
On a Dell 4400, 1.6ghz pci based system which has two ethernet cards
installed, running 32 bit FC5 latest kernel, 2.6.17-1.2139_FC5,  I
have the following emergency.
(This machine was upgraded from FC4 to FC5 yesterday and was rebooted
yesterday, a-ok, before the current problem struck.)
My config did NOT use eth1 (was deactivated), only eth0, and was the
only nic physically connected to the router. Tonight after a reboot,
this cpu ceased seeing the lan, and others coudn't ping it as well.
Fiddling around in back of the machine I noticed that the eth0 card
was loose in the socket. I brought down the system, re-inserted the
card, but still didn't work. So, I assumed that maybe the card burnt
out since it was loose. No sweat, I thought, that is why I have the
spare nic. I ran the networking applet,
deactivated eth0, activated (and plugged in) eth1, tried service
network restart, it showed eth1[ok] but.... no bytes, 0, nadda. Same
after a reboot.
I then copied /etc/sysconfig/networking/devices/ifcfg-eth0 over to
ifcfg-eth1, UNPLUGGED eth0 from the router, set the ip address in eth1
to the same as eth0 had, rebooted but still -NADDA-.
The queer thing is that it insists the both eth0 and eth1 are active,
regardless as to how I set it via the applet. (It reverts to active.)
Fwiw, I do NOT have the NetworkServices daemon active.
Hopefully I missed doing something elementary.
Your help is mostly appreciated.
-nat