Today got server freezes. In log last message:
Nov 15 23:04:05 !!! kernel: [433562.050053] ------------[ cut here ]------------
Nov 15 23:04:05 !!! kernel: [433562.050070] WARNING: at /build/buildd/linux-2.6.31/net/sched/sch_generic.c:246 dev_watchdog+0x262/0x270()
Nov 15 23:04:05 !!! kernel: [433562.050073] Hardware name: PowerEdge 1950
Nov 15 23:04:05 !!! kernel: [433562.050075] NETDEV WATCHDOG: eth0 (bnx2): transmit queue 0 timed out
Nov 15 23:04:05 !!! kernel: [433562.050082] Modules linked in: mii usbhid iptable_raw ufs qnx4 hfsplus hfs minix ntfs vfat msdos fat jfs xfs exportfs reiserfs sch_prio act_police cls_u32 sch_ingress sch_tbf pptp pppoe pppox bonding xt_recent xt_state xt_tcpudp iptable_nat nf_nat nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 iptable_mangle radeon ttm drm bnx2 i5000_edac iptable_filter edac_core dell_wmi psmouse i2c_algo_bit ip_tables lp i5k_amb serio_raw dcdbas shpchp x_tables parport mptsas mptscsih mptbase scsi_transport_sas e1000e [last unloaded: sky2]
Nov 15 23:04:05 !!! kernel: [433562.050146] Pid: 0, comm: swapper Not tainted 2.6.31-14-server #48-Ubuntu
Nov 15 23:04:05 !!! kernel: [433562.050148] Call Trace:
Nov 15 23:04:05 !!! kernel: [433562.050150] [] warn_slowpath_common+0x78/0xb0
Nov 15 23:04:05 !!! kernel: [433562.050164] [] warn_slowpath_fmt+0x3c/0x40
Nov 15 23:04:05 !!! kernel: [433562.050166] [] dev_watchdog+0x262/0x270
Nov 15 23:04:05 !!! kernel: [433562.050177] [] ? destroy_conntrack+0xb6/0xf0 [nf_conntrack]
Nov 15 23:04:05 !!! kernel: [433562.050181] [] ? nf_conntrack_destroy+0x12/0x20
Nov 15 23:04:05 !!! kernel: [433562.050188] [] ? death_by_timeout+0x84/0x150 [nf_conntrack]
Nov 15 23:04:05 !!! kernel: [433562.050191] [] ? scheduler_tick+0x123/0x270
Nov 15 23:04:05 !!! kernel: [433562.050193] [] ? dev_watchdog+0x0/0x270
Nov 15 23:04:05 !!! kernel: [433562.050197] [] run_timer_softirq+0x16c/0x270
Nov 15 23:04:05 !!! kernel: [433562.050200] [] __do_softirq+0xbd/0x200
Nov 15 23:04:05 !!! kernel: [433562.050203] [] call_softirq+0x1c/0x30
Nov 15 23:04:05 !!! kernel: [433562.050206] [] do_softirq+0x55/0x90
Nov 15 23:04:05 !!! kernel: [433562.050208] [] irq_exit+0x85/0x90
Nov 15 23:04:05 !!! kernel: [433562.050211] [] smp_apic_timer_interrupt+0x6c/0xa0
Nov 15 23:04:05 !!! kernel: [433562.050215] [] apic_timer_interrupt+0x13/0x20
Nov 15 23:04:05 !!! kernel: [433562.050216] [] ? mwait_idle+0x7c/0x120
Nov 15 23:04:05 !!! kernel: [433562.050227] [] ? atomic_notifier_call_chain+0x15/0x20
Nov 15 23:04:05 !!! kernel: [433562.050230] [] ? cpu_idle+0xb2/0x100
Nov 15 23:04:05 !!! kernel: [433562.050234] [] ? rest_init+0x66/0x70
Nov 15 23:04:05 !!! kernel: [433562.050239] [] ? start_kernel+0x352/0x35b
Nov 15 23:04:05 !!! kernel: [433562.050241] [] ? x86_64_start_reservations+0x125/0x129
Nov 15 23:04:05 !!! kernel: [433562.050243] [] ? x86_64_start_kernel+0xfa/0x109
Nov 15 23:04:05 !!! kernel: [433562.050246] ---[ end trace ac522a1b002f7a69 ]---

How I can solve this problem? Server freezes randomly, but usually I don't get messages in log, but on console I can see Soft lockup.