I sent all logs from maintenance tests to HP support and they told that there is no problems with hardware.
And they suggested to update NIC drivers and if that not help - to contact with vmware support team.
Okay, I found new drivers.
Here they are:
http://downloads.vmware.com/d/details/dt_esx41_broadcom_netxtremeii_032311/ZHcqYnR0anBiZCpwcA
The ESX Server 4.1 driver CD includes support for version bnx2i-1.9.1t.v41.2, bnx2-2.0.22f.v41.2,bnx2x-1.62.15.v41.2, cnic-1.10.2q.v41.9 on ESX/ESXi.
I checked my esxi - it is 4.1 build 433742.
From console I checked versions of drivers:
~ # ethtool -i vmnic0
driver: bnx2
version: 2.0.7d-4vmw
firmware-version: 5.2.3 NCSI 2.0.6
bus-info: 0000:02:00.0
~ # ethtool -i vmnic4
driver: e1000e
version: 1.1.2-NAPI
firmware-version: 5.12-2
bus-info: 0000:0f:00.0
~ #
I got old one drivers.
That means that this drivers update applyes to my esxi.
Also I've got vmware update manager. Is it possible to find this drivers update in update manager? I have not found it there.