$client = new SforceEnterpriseClient();
$client->setSessionHeader(...);
/*
Throws following error:
ValueError: SoapHeader::__construct(): Argument #1 ($namespace) cannot be empty in /vendor/developerforce/force.com-toolkit-for-php/soapclient/SforceBaseClient.php:377
*/
Word-around
$client = new SforceEnterpriseClient();
$client->SforceEnterpriseClient();
$client->setSessionHeader(...);
Throws Error
Word-around