Upgraded to ubuntu 2.6.27-11.25-generic and the network stopped working.
I found this using dmesg
[ 131.816023] ------------[ cut here ]------------
[ 131.816037] WARNING: at /build/buildd/linux-2.6.27/net/sched/sch_generic.c:219 dev_watchdog+0x21a/0x230()
[ 131.816044] NETDEV WATCHDOG: eth0 (r8169): transmit timed out
[ 131.816049] Modules linked in: ppdev cpufreq_userspace cpufreq_stats cpufreq_powersave cpufreq_conservative cpufreq_ondemand freq_table video output wmi pci_slot container sbs sbshc battery ipv6 af_packet iptable_filter ip_tables x_tables ac lp loop snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss evdev snd_seq_midi parport_pc parport snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device button snd iTCO_wdt pcspkr iTCO_vendor_support soundcore snd_page_alloc intel_agp agpgart shpchp pci_hotplug ext3 jbd mbcache sd_mod crc_t10dif sg ata_generic ata_piix usbhid hid pata_acpi libata scsi_mod dock ehci_hcd r8169 mii uhci_hcd usbcore thermal processor fan fbcon tileblit font bitblit softcursor fuse
[ 131.816175] Pid: 0, comm: swapper Not tainted 2.6.27-11-generic #1
[ 131.816182] [<c0131e15>] warn_slowpath+0x65/0x90
[ 131.816193] [<c02ebf88>] ? skb_release_data+0x68/0xa0
[ 131.816203] [<c02ebe16>] ? __kfree_skb+0x36/0x90
[ 131.816211] [<c037edde>] ? account_scheduler_latency+0xe/0x220
[ 131.816222] [<c037edde>] ? account_scheduler_latency+0xe/0x220
[ 131.816231] [<c014e6eb>] ? getnstimeofday+0x4b/0x100
[ 131.816241] [<c014e6eb>] ? getnstimeofday+0x4b/0x100
[ 131.816249] [<c0136a26>] ? set_normalized_timespec+0x16/0x90
[ 131.816258] [<c0154437>] ? timer_stats_update_stats+0x17/0x250
[ 131.816267] [<c0254a19>] ? strlen+0x9/0x20
[ 131.816276] [<c0252a9d>] ? strlcpy+0x1d/0x60
[ 131.816284] [<c02f16a7>] ? netdev_drivername+0x37/0x40
[ 131.816293] [<c03068aa>] dev_watchdog+0x21a/0x230
[ 131.816301] [<c0106d0f>] ? profile_pc+0x3f/0x50
[ 131.816310] [<c014dac7>] ? profile_tick+0x57/0x90
[ 131.816319] [<c01537d0>] ? tick_sched_timer+0x60/0xc0
[ 131.816327] [<c013c038>] run_timer_softirq+0x138/0x210
[ 131.816336] [<c0306690>] ? dev_watchdog+0x0/0x230
[ 131.816344] [<c0306690>] ? dev_watchdog+0x0/0x230
[ 131.816369] [<c0137732>] __do_softirq+0x92/0x120
[ 131.816376] [<c013781d>] do_softirq+0x5d/0x60
[ 131.816383] [<c0137995>] irq_exit+0x55/0x90
[ 131.816390] [<c0113f8d>] smp_apic_timer_interrupt+0x5d/0x90
[ 131.816399] [<c01050f8>] apic_timer_interrupt+0x28/0x30
[ 131.816408] [<c010acca>] ? mwait_idle+0x4a/0x50
[ 131.816416] [<c010288d>] cpu_idle+0x7d/0x140
[ 131.816423] [<c036fbe3>] rest_init+0x53/0x60
[ 131.816431] =======================
[ 131.816435] ---[ end trace c20439a3b7737fa3 ]---
