Are you running on windows? If so I've run into the same basic problem you have and it seems to be a bug with the PDO extension:
PHP Bugs: #39759: Can't use stored procedures from PDO on Windows
To get around this on windows I have the following code:
PHP Code:
if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
$this->dbObj->closeConnection();
}
A hack for sure, but it works
.
Hope that helps