No network after upgrading to pve-kernel-2.6.32-19-pve

Today I have lost one box after upgrade to get a newer kernel with apt-get dist-upgrade,
the server was alive, but network was not reachable.

Here comes the kernel log output
May 26 10:01:40 proxmox2 kernel: r8169 0000:04:00.0: firmware: requesting rtl_nic/rtl8168e-3.fw
May 26 10:01:40 proxmox2 kernel: r8169 0000:04:00.0: eth0: unable to load firmware patch rtl_nic/rtl8168e-3.fw (-2)
May 26 10:01:40 proxmox2 kernel: r8169 0000:04:00.0: eth0: link down
May 26 10:01:40 proxmox2 kernel: r8169 0000:04:00.0: eth0: link down

The network card is onboard Realtek:
04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
Subsystem: Micro-Star International Co., Ltd. Device 7693

Booting the old kernel with flavour 18-pve worked for me.