Looks like its a 32bit shared library, not 64 (despite the name). 

I would try reinstalling LibXML with CPAN.

I have the same error on a Centos 5.6 machine with the Vsphere 4.1 SDK. When i tried to check the status of my ESX Server with nagios i have that problem:

/usr/local/icinga/libexec/check_esx.pl -H 192.168.xxx.xxx -u xxxxxxxx -p xxxxxxxxxxxx -l cpu
CHECK_ESX.PL  CRITICAL - Server version unavailable at  'https://192.168.xxx.xxx:443/sdk/vimService.wsdl' at  /usr/lib/perl5/5.8.8/VMware/VICommon.pm line 545.

I check the Vsphere 4.1 SDK Documentation and i had already install all the requirments (Perl Modules, Openssl and libxml2).

I tried to re-install the XML::LibXML without results

Find out what module path is being loaded.  LibXML is common and often loaded multiple times...though usually I see the problem with Windows, not with Nix.

Check your %INC for the LibXML module, make sure it's the one you want to use.

I had the same problem ( CHECK_ESX CRITICAL - Server version unavailable ), and I spent a lot of time searching.  Most of the suggestions were to set the environment variable to tell the IO::Socket::SSL to not check the self-signed certificate (adding the following line near the top of the check_esx script):

$ENV{SSL_verify_mode} = 0x00;

This didn't work for me, and after much debugging I figured out that the script isn't using IO::Socket::SSL -- it's using LWP.  The proper change to check_esx when using LWP is:

$ENV{PERL_LWP_SSL_VERIFY_HOSTNAME} = 0;

I put it after the line  use File::Basename;  so it looks like:

use Nagios::Plugin;
use File::Basename;

$ENV{PERL_LWP_SSL_VERIFY_HOSTNAME} = 0;

my $perl_module_instructions="
Download the latest version of Perl Toolkit from VMware support page.

After making this change, the check_esx plugin again works perfectly.

Additionally, please note that this worked fine for me previously - it only broke after my last yum update on my CentOS server hosting Nagios.

I have the same problem.

It's not necessary to modify any file. Just restart mgmt-vmware service on remote server and try again.

/etc/init.d/mgmt-vmware restart

I had a similar problem and believe this is an issue related to the latest version of a more recent LWP::UserAgent Perl module (above 6.x).

Adding the following to my environment fixed errors related to /usr/lib/perl5/5.8.8/VMware/VICommon.pm

export PERL_LWP_SSL_VERIFY_HOSTNAME=0

im have this error

root@hostname# ./check_esx3-0.5.orig.pl -H Hostname -u nagios -p User -l cpu -s usage -w85 -c90

CHECK_ESX3-0.5.ORIG.PL CRITICAL - Error: Server version unavailable at 'https://hostname:443/sdk/vimService.wsdl'

how im can fix it ?