in Protocol.php in line 73
PEAR::isError() is not a static method
PEAR Version: 1.9.4
PHP Version: 5.3.16
OS Windows 7
I fixed this by creating an object:
$pear = new PEAR;
if ($pear->isError($hdr = Net_EPP_Protocol::_fread_nb($socket,4))) {
return $hdr;
}