I can cnofirm that the latest update (using kernel 2.6.31-14-generic)
appears to have fixed the problem.

On Sun, 01 Nov 2009 22:25:11 -0000, William King <email address hidden>
wrote:
> I can confirm that it is fixed in 9.10.
> 
> On Sun, Nov 1, 2009 at 2:02 PM, amspilot <email address hidden> wrote:
>> Hi Nicolas,
>>
>> Sorry to say, but i have not had the time to do an update as just jet,
>> so i can not denny or confirm that the problem is solved in u9.10.
>>
>> but i am sertanly going to do this a lot sooner now jou have reported
>> that the problem was solved.
>>
>> thanks for you feedback,
>>
>> best Regards,
>>
>> Dave.
>>
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>> bestanden is strikt vertrouwelijk en uitsluitend bestemd voor de
>> geadresseerde. Gebruik van deze inhoud door anderen zonder toestemming
>> van de afzender of de geadresseerde is onrechtmatig.
>>
>> This message and any other enclosed documents are strictly confidential
>> and intended for the addressee only. Any use by others without the
>> consent of the sender or the addressee is unlawful.
>>
>>
>> --- On Sun, 11/1/09, Nicolas Picard <email address hidden> wrote:
>>
>>> From: Nicolas Picard <email address hidden>
>>> Subject: [Bug 347711] Re: Realtek RTL8111/8168B PCI Express Gigabit
> Ethernet controller Unstable on Jaunty
>>> To: <email address hidden>
>>> Date: Sunday, November 1, 2009, 6:32 AM
>>> Well, as expected, I upgraded from
>>> Jaunty to Karmic and that annoying
>>> problem is now gone. Data transferts no longer stop and
>>> time out. I'm
>>> using Intel D945GCLF2 board. So... is it fine on yours side
>>> ? I thinks
>>> that we can close that bug now.
>>>
>>> --
>>> Realtek RTL8111/8168B PCI Express Gigabit Ethernet
>>> controller Unstable on Jaunty
>>> https://bugs.launchpad.net/bugs/347711
>>> You received this bug notification because you are a direct
>>> subscriber
>>> of the bug.
>>>
>>> Status in The Linux Kernel: Incomplete
>>> Status in “linux” package in Ubuntu: Incomplete
>>>
>>> Bug description:
>>> Binary package hint: linux-image-2.6.28-11-generic
>>>
>>> Related to this bug:
>>>
>>> http://bugzilla.kernel.org/show_bug.cgi?id=12411
>>>
>>> andres@testinserver1:~$ lsb_release -rd
>>> Description:    Ubuntu jaunty (development
>>> branch)
>>> Release:        9.04
>>>
>>> Mainboard/Processor: D945GCLF2 / Atom 330
>>>
>>> Network unstable on the latest kernel, worked fine on
>>> Intrepid Ibex.
>>> Network goes down even though mii-tool still says
>>> negotiated, appears to be related to the network
>>> driver/adapter which is:
>>>
>>> 01:00.0 Ethernet controller: Realtek Semiconductor Co.,
>>> Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller
>>> (rev 02)
>>>
>>> Dmesg output
>>>
>>> [  284.816023] ------------[ cut here ]------------
>>> [  284.816032] WARNING: at
>>> /build/buildd/linux-2.6.28/net/sched/sch_generic.c:226
>>> dev_watchdog+0x219/0x230()
>>> [  284.816038] NETDEV WATCHDOG: eth2 (r8169): transmit
>>> timed out
>>> [  284.816042] Modules linked in: binfmt_misc i915 drm
>>> bridge stp bnep video output input_polldev smsc47m1
>>> smsc47m192 hwmon_vid i2c_i801 sbp2 ieee1394 lp snd_hda_intel
>>> snd_pcm_oss snd_mixer_oss snd_pcm ppdev snd_seq_dummy
>>> snd_seq_oss snd_seq_midi iTCO_wdt iTCO_vendor_support
>>> snd_rawmidi psmouse pcspkr snd_seq_midi_event serio_raw
>>> snd_seq snd_timer snd_seq_device parport_pc parport snd
>>> intel_agp soundcore snd_page_alloc agpgart usbhid
>>> usb_storage r8169 mii fbcon tileblit font bitblit
>>> softcursor
>>> [  284.816119] Pid: 4, comm: ksoftirqd/0 Not tainted
>>> 2.6.28-11-generic #37-Ubuntu
>>> [  284.816123] Call Trace:
>>> [  284.816135]  [<c0139a60>]
>>> warn_slowpath+0x60/0x80
>>> [  284.816143]  [<c0156873>] ?
>>> getnstimeofday+0x53/0x110
>>> [  284.816151]  [<c0119aa3>] ?
>>> lapic_next_event+0x13/0x20
>>> [  284.816158]  [<c0159aaa>] ?
>>> clockevents_program_event+0x9a/0x150
>>> [  284.816165]  [<c0156873>] ?
>>> getnstimeofday+0x53/0x110
>>> [  284.816172]  [<c02caded>] ?
>>> strlcpy+0x1d/0x60
>>> [  284.816180]  [<c04313b2>] ?
>>> netdev_drivername+0x32/0x40
>>> [  284.816186]  [<c0445f19>]
>>> dev_watchdog+0x219/0x230
>>> [  284.816193]  [<c0156873>] ?
>>> getnstimeofday+0x53/0x110
>>> [  284.816199]  [<c0119aa3>] ?
>>> lapic_next_event+0x13/0x20
>>> [  284.816206]  [<c0159aaa>] ?
>>> clockevents_program_event+0x9a/0x150
>>> [  284.816214]  [<c0143aa0>]
>>> run_timer_softirq+0x130/0x200
>>> [  284.816220]  [<c0445d00>] ?
>>> dev_watchdog+0x0/0x230
>>> [  284.816226]  [<c0445d00>] ?
>>> dev_watchdog+0x0/0x230
>>> [  284.816233]  [<c013f147>]
>>> __do_softirq+0x97/0x170
>>> [  284.816240]  [<c0152c36>] ?
>>> hrtimer_interrupt+0x186/0x1b0
>>> [  284.816246]  [<c013f27d>]
>>> do_softirq+0x5d/0x60
>>> [  284.816253]  [<c013f3f5>]
>>> irq_exit+0x55/0x90
>>> [  284.816259]  [<c011a0ab>]
>>> smp_apic_timer_interrupt+0x5b/0x90
>>> [  284.816266]  [<c0105318>]
>>> apic_timer_interrupt+0x28/0x30
>>> [  284.816274]  [<c012f9ae>] ?
>>> finish_task_switch+0x2e/0xe0
>>> [  284.816281]  [<c050106a>]
>>> schedule+0x41a/0x710
>>> [  284.816288]  [<c013f35d>]
>>> ksoftirqd+0xdd/0x120
>>> [  284.816294]  [<c013f280>] ?
>>> ksoftirqd+0x0/0x120
>>> [  284.816300]  [<c014e8ac>]
>>> kthread+0x3c/0x70
>>> [  284.816306]  [<c014e870>] ?
>>> kthread+0x0/0x70
>>> [  284.816312]  [<c0105477>]
>>> kernel_thread_helper+0x7/0x10
>>> [  284.816317] ---[ end trace ebee70bd161e4e23 ]---
>>> [  284.832839] r8169: eth2: link up
>>> [  296.832701] r8169: eth2: link up
>>> [  321.016744] r8169: eth2: link up
>>> [  681.016709] r8169: eth2: link up
>>> [ 3231.016736] r8169: eth2: link up
>>>
>>> It's stable for one hour if i force to 100mbps full
>>> duplex.
>>>
>>> Other network gear working fine
>>>
>>
>> --
>> Realtek RTL8111/8168B PCI Express Gigabit Ethernet controller Unstable
> on Jaunty
>> https://bugs.launchpad.net/bugs/347711
>> You received this bug notification because you are a direct subscriber
>> of the bug.
>>
>> Status in The Linux Kernel: Incomplete
>> Status in “linux” package in Ubuntu: Incomplete
>>
>> Bug description:
>> Binary package hint: linux-image-2.6.28-11-generic
>>
>> Related to this bug:
>>
>> http://bugzilla.kernel.org/show_bug.cgi?id=12411
>>
>> andres@testinserver1:~$ lsb_release -rd
>> Description:    Ubuntu jaunty (development branch)
>> Release:        9.04
>>
>> Mainboard/Processor: D945GCLF2 / Atom 330
>>
>> Network unstable on the latest kernel, worked fine on Intrepid Ibex.
>> Network goes down even though mii-tool still says negotiated, appears to
> be related to the network driver/adapter which is:
>>
>> 01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd.
> RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 02)
>>
>> Dmesg output
>>
>> [  284.816023] ------------[ cut here ]------------
>> [  284.816032] WARNING: at
> /build/buildd/linux-2.6.28/net/sched/sch_generic.c:226
> dev_watchdog+0x219/0x230()
>> [  284.816038] NETDEV WATCHDOG: eth2 (r8169): transmit timed out
>> [  284.816042] Modules linked in: binfmt_misc i915 drm bridge stp bnep
> video output input_polldev smsc47m1 smsc47m192 hwmon_vid i2c_i801 sbp2
> ieee1394 lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm ppdev
> snd_seq_dummy snd_seq_oss snd_seq_midi iTCO_wdt iTCO_vendor_support
> snd_rawmidi psmouse pcspkr snd_seq_midi_event serio_raw snd_seq snd_timer
> snd_seq_device parport_pc parport snd intel_agp soundcore snd_page_alloc
> agpgart usbhid usb_storage r8169 mii fbcon tileblit font bitblit
softcursor
>> [  284.816119] Pid: 4, comm: ksoftirqd/0 Not tainted 2.6.28-11-generic
> #37-Ubuntu
>> [  284.816123] Call Trace:
>> [  284.816135]  [<c0139a60>] warn_slowpath+0x60/0x80
>> [  284.816143]  [<c0156873>] ? getnstimeofday+0x53/0x110
>> [  284.816151]  [<c0119aa3>] ? lapic_next_event+0x13/0x20
>> [  284.816158]  [<c0159aaa>] ? clockevents_program_event+0x9a/0x150
>> [  284.816165]  [<c0156873>] ? getnstimeofday+0x53/0x110
>> [  284.816172]  [<c02caded>] ? strlcpy+0x1d/0x60
>> [  284.816180]  [<c04313b2>] ? netdev_drivername+0x32/0x40
>> [  284.816186]  [<c0445f19>] dev_watchdog+0x219/0x230
>> [  284.816193]  [<c0156873>] ? getnstimeofday+0x53/0x110
>> [  284.816199]  [<c0119aa3>] ? lapic_next_event+0x13/0x20
>> [  284.816206]  [<c0159aaa>] ? clockevents_program_event+0x9a/0x150
>> [  284.816214]  [<c0143aa0>] run_timer_softirq+0x130/0x200
>> [  284.816220]  [<c0445d00>] ? dev_watchdog+0x0/0x230
>> [  284.816226]  [<c0445d00>] ? dev_watchdog+0x0/0x230
>> [  284.816233]  [<c013f147>] __do_softirq+0x97/0x170
>> [  284.816240]  [<c0152c36>] ? hrtimer_interrupt+0x186/0x1b0
>> [  284.816246]  [<c013f27d>] do_softirq+0x5d/0x60
>> [  284.816253]  [<c013f3f5>] irq_exit+0x55/0x90
>> [  284.816259]  [<c011a0ab>] smp_apic_timer_interrupt+0x5b/0x90
>> [  284.816266]  [<c0105318>] apic_timer_interrupt+0x28/0x30
>> [  284.816274]  [<c012f9ae>] ? finish_task_switch+0x2e/0xe0
>> [  284.816281]  [<c050106a>] schedule+0x41a/0x710
>> [  284.816288]  [<c013f35d>] ksoftirqd+0xdd/0x120
>> [  284.816294]  [<c013f280>] ? ksoftirqd+0x0/0x120
>> [  284.816300]  [<c014e8ac>] kthread+0x3c/0x70
>> [  284.816306]  [<c014e870>] ? kthread+0x0/0x70
>> [  284.816312]  [<c0105477>] kernel_thread_helper+0x7/0x10
>> [  284.816317] ---[ end trace ebee70bd161e4e23 ]---
>> [  284.832839] r8169: eth2: link up
>> [  296.832701] r8169: eth2: link up
>> [  321.016744] r8169: eth2: link up
>> [  681.016709] r8169: eth2: link up
>> [ 3231.016736] r8169: eth2: link up
>>
>> It's stable for one hour if i force to 100mbps full duplex.
>>
>> Other network gear working fine
>>
> 
>