10.5.8 does not resume wired ehternet after resume from sleep.

Question

I am new to administering macs but have many years linux experience.
I have a imac here that does not correctly wake from sleep.
It assumes an generic IPV4 address instead of resuming its lease.
Here is some data from the kernel buffer running dmesg:
previous Sleep Cause: 0
Ethernet [AppleYukon2]: Link up on en0, 100-Megabit, Half-duplex, No flow-control, Debug [796d,4c08,0de1,0200,40a1,4000]
0 [Time 1271523730] [Message System Sleep
Wake reason = EHC1 EHC2
System Wake
Previous Sleep Cause: 0
USB (EHCI):Port 2 on bus 0xfa has remote wakeup from some device
Ethernet [AppleYukon2]: Link up on en0, 100-Megabit, Half-duplex, No flow-control, Debug [796d,4c08,0de1,0200,40a1,4000]
Ethernet [AppleYukon2]: Link up on en0, 100-Megabit, Half-duplex, No flow-control, Debug [796d,4c08,0de1,0200,40a1,4000]
[/code]
Things I have tried:
Searching here in these forums.
I have set the networking order in system > prefrences to put en0 first.
and disabled other services, network sharing, ipv6 etc.
I can correct the problem in the terminal using:
ifconfig en0 down
ifconfig en0 inet 192.168.0.2
ifconfig en0 up
however this is obviously not satisfactory for the user.
I read another post here about a 2nd dhcp being installed and conflicting with dhcp.
I am not sure how to check this but appears to be a dhcping: here is the output of locate:
locate dhcping
/opt/local/var/macports/sources/rsync.macports.org/release/ports/net/dhcping
/opt/local/var/macports/sources/rsync.macports.org/release/ports/net/dhcping/Por tfile
However I do not think it is "active" as which dhcp does not return anything.
Where are networking configuration files stored?
Is there somewhere I can set the IPV4 fallback IP address?
Or how about setting the DHCP timeout?
Thanks for any input / ideas.

Answer 1

Hmm thanks I have tried to reset the lease and looked at the advanced settings.
Nothing in the network pane fixes the problem reliably.
I suggested the same option to the user with the sleep issue and that solution was rejected as it saves more energy send the kernel into sleep mode.
The problem seems to have appeared after a update to 10.5.8.
Perhaps I will try to revert the computer back to 10.5.7. to see if the issue goes away?
Is there a "package manager" (like portage or apt-get?) for OSX system applications or is it just a release?
Perhaps I could just revert the DHCP application or the network manager as on linux?
Here is a link to that other post: http://discussions.info.apple.com/thread.jspamessageID=11088284&#11088284