eth0 continually restarts

[saran]

This problem has been happening since 8.10. ( 8.04 and previous were fine ). eth0 keeps going down every few seconds. Not an NIC problem as it works fine under windows. From the dmesg output, i thought the Flow Control thing could be a problem, but even though i changed it to 100baseTX-FD, (or HD) using mii-tool, it goes back to default auto-negotiate mode.

Any help is welcome.
Please let me know if you need any info about my laptop.
( Which is a run-off-the-mill Dell Inspiron 6400 )

Update : Someone else also has a similar problem.
http://ubuntuforums.org/showthread.php?t=1140903&highlight=b44+eth0+unstable

Here are some details.

[ 783.559994] b44: eth0: powering down PHY
[ 784.000159] b44: eth0: Link is down.
[ 787.000247] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 787.000254] b44: eth0: Flow control is off for TX and off for RX.
[ 908.149321] b44: eth0: powering down PHY
[ 909.000149] b44: eth0: Link is down.
[ 911.000237] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 911.000245] b44: eth0: Flow control is off for TX and off for RX.
[ 948.441529] b44: eth0: powering down PHY
[ 949.000151] b44: eth0: Link is down.
[ 952.000233] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 952.000241] b44: eth0: Flow control is off for TX and off for RX.
[ 997.297579] b44: eth0: powering down PHY
[ 998.000190] b44: eth0: Link is down.
[ 1000.000236] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 1000.000244] b44: eth0: Flow control is off for TX and off for RX.
[ 1041.604031] b44: eth0: powering down PHY
[ 1042.000153] b44: eth0: Link is down.
[ 1045.000238] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 1045.000245] b44: eth0: Flow control is off for TX and off for RX.
[ 1117.120571] b44: eth0: powering down PHY
[ 1118.000142] b44: eth0: Link is down.
[ 1120.000236] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 1120.000244] b44: eth0: Flow control is off for TX and off for RX.
[ 1203.072481] b44: eth0: powering down PHY
[ 1204.000147] b44: eth0: Link is down.
[ 1206.004217] b44: eth0: Link is up at 100 Mbps, full duplex.
[ 1206.004224] b44: eth0: Flow control is off for TX and off for RX.

*-network
description: Ethernet interface
product: BCM4401-B0 100Base-TX
vendor: Broadcom Corporation
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth0
version: 02
serial: 00:15:c5:c4:f5:3a
width: 32 bits
clock: 33MHz
capabilities: bus_master cap_list ethernet physical
configuration: broadcast=yes driver=b44 driverversion=2.0 latency=64 module=ssb multicast=yes