ZFS Permanent errors on fresh installation on VMware ESX

[Zeus Panchenko]

hi,

may somebody advise, please?

FreeBSD 9.2R just installed on VM under VMware ESX 4.1.2
CPU: 2x1.5GHz
MEM: 1G
HDD: 16Gb

> uname -a
FreeBSD 9.2-RELEASE #0 r255898: amd64

vfs.zfs.arc_max=536870912

open-vm-tools-nox11-425873_3,1 port is intsalled 

after portinstall of several ports, reboot and scrub, status shows this:

  pool: zroot
 state: ONLINE
status: One or more devices has experienced an error resulting in data
        corruption.  Applications may be affected.
action: Restore the file in question if possible.  Otherwise restore the
        entire pool from backup.
   see: http://illumos.org/msg/ZFS-8000-8A
  scan: scrub repaired 0 in 0h2m with 2 errors on Mon Sep 30 20:00:01 2013
config:

        NAME         STATE     READ WRITE CKSUM
        zroot        ONLINE       0     0     2
          gpt/disk0  ONLINE       0     0     4

errors: Permanent errors have been detected in the following files:

        /usr/ports/distfiles/gnome2/glib-2.36.3.tar.xz
        /usr/src/contrib/gcc/ChangeLog-2005


how is it possible on just installed system?

what can be the cause?

other OSes (MSWin, Centos,Debian) works fine, but FreeBSD on ZFS (and even UFS)
exposes disk damages :(

is there some "secret" knowledge to manage fs on VM installations?

-- 
Zeus V. Panchenko				jid:zeus at im.ibs.dn.ua
IT Dpt., I.B.S. LLC					  GMT+2 (EET)