What sorts of error messages do you get?

In german:
IP-Informationen werden fuer eth0 bestimmt... fehlgeschlagen; keine Verbindung
vorhanden. Kabel pruefen?

In english this would be something like:
Getting IP-information for eth0... no answer; no connection. Check cable?

(from both the dhcp client, and the kernel)

Bill, in case your last comment was meant as an addtional question:
I only see the error message at boot time or when running "ifup eth0". Nothing
unusual in /var/log/messages. The sis900 kernel module is loaded correctly and I
even can get network up and running when manually running "ifconfig".

*** Bug 80351 has been marked as a duplicate of this bug. ***

Oddly enough, running dhclient by hand works.  Something is odd with the init
scripts.  Running the graphical network config tool... and attempting to
"activate" device causes the net-config program to crash with a runtime error.

As a work around, I'm putting /sbin/dhclient in the rc.local.

Hmmm, maybe I'm talking-out-my-ass here... but this stuff seems to be related to
trying to pass a hostname to dhclient?  I don't know.  Whatever I do to try and
automate getting an IP address via DHCP (adding it to rc.local, or willy-nilly
editing the /sbin/ifup script to just run dhclient without any parameters)...
sure, it gets and address and networking works... but something about the
environment doesn't get set right and I can't login to X.  Sucks.  Yeah, I
know.. I provided no details.  What is a proper workaround to this problem?

Oh, well... betas are for fixing stuff.  In any event, it's definitely something
in the /sbin/ifup script.

There's stuff in the initscript (see the network-functions file) that checks for
a link before starting dhcp, because it's somewhat silly to sit waiting on dhcp
when there's no cable. Apparently, this code isn't working right on sis900 cards
for some reason.

I did some poking around and this is what I have found out.

1. the initscript works IF you "ifconfig eth0 up" first

2. The problems seem to be in /etc/sysconfig/network-scripts/network-functions
shell library.

Within the function check_link_down there is an IF branch that has a preceding
not (!) operator looking to see if LC_ALL is set to "C". Problem is in the same
function library the is_available function does 

LC_ALL= LANG= ip -o link | grep -q $1

Which results in LC_ALL being set to nothing. So, when the check_link_down
function runs with the following logic (excuse the echos, that is from me trying
to find out what is going on)

echo "function start"
    if [ -x /sbin/mii-tool ]; then
        echo "branch executed"
        echo $LC_ALL
        if ! LC_ALL=C ip link show $1 2>/dev/null| grep -q UP ; then
           ip link set $1 up >/dev/null 2>&1
           echo "Check link up"
           ifconfig eth0
           timeout=0
           while [ $timeout -le 20 ]; do
                LC_ALL=C ip link show $1 2>/dev/null | grep -q UP && break
                usleep 500000
                timeout=$((timeout+1))
           done
        fi


The second if block does not get executed as it should. I've been able to fix
the problem by taking out the "!".

I don't consider myself an expert shell programmer. There seems to be something
in the way that the SIS adapter reports text within "ip -o link" that does not
set the LC_ALL variable to "C". What it is I cannot say because that is the only
adapter I have. 

Anyhow, that's my analysis. BTW...what the the LC_ALL variable for anyhow?

Err....

I think I may have the logic in my analysis reversed when talking about the "!".
I hate thinking about reverse logic. That's what I get for looking at this thing
on a late sunday night after 3 beers.

Anyhow. I hope that clears any confusion

*** Bug 80731 has been marked as a duplicate of this bug. ***

this bug happens in my RedHat 8.0 version (the one that is avaliable to 
download but is not the beta one). My card is a 3Com 3C905B. This but is not 
only for SIS cards - I think all NICs a affected. And is not only in the BETA 
PHOEBE, for shure! Manually running the dhcpclient solves the problem! I got 
this same EXACT BUG!

sorry for my VERY BAD English, I'm from Brazil and it's 2:38 of the morning. =]

Fwiw, on the systems I use, they all work on RHL 8.0. Including the SiS one.
With the phoebe beta, all systems except the SiS one work.

Will be fixed in 7.03-1.

Fix confirmed.

Indeed, fix confirmed for me under Phoebe2 too.

*** Bug 83010 has been marked as a duplicate of this bug. ***