Snmpset with Perl problem

This works with CISCO-VTP-MIB.my ->>

rchadda@office1:~/mibs$ snmpset -v 1 -c public x.x.x.x
vtpVlanEditDot10Said.1.22 x 000186B6

But can't get the Perl Syntax right :((

$varbind = new
SNMP::Varbind(['vtpVlanEditDot10Said',1.22,'0x000186B6','x']);
$session->set($varbind);
if ($session->{'ErrorNum'}) {
print "DBG: SNMP error: " . $session->{'ErrorStr'} . "\n";

}

says:
DBG: SNMP error: (badValue) The value given has the wrong type or
length.

Please help.