Description:
------------
instanceof fails to detect that an object is an instance of OCI-Lob (possibly due to the hyphen?)

deprecated function is_a() works correctly with a value of is

Reproduce code:
---------------
    $conn = oci_connect('username', 'password', 'database');

    $lob = oci_new_descriptor($conn, OCI_D_LOB);

    if ($lob instanceof OCI-Lob) {
        echo 'instanceof says $lob IS an OCI-Lob<br />';
    } else {
        echo 'instanceof says $lob is NOT an OCI-Lob!<br />';
    }

    if (is_a($lob, 'OCI-Lob')) {
        echo 'is_a says $lob IS an OCI-Lob<br />';
    } else {
        echo 'is_a says $lob is NOT an OCI-Lob!<br />';
    }

    echo '$lob is: ' . get_class($lob) . '<br />';

Expected result:
----------------
instanceof says $lob IS an OCI-Lob!
is_a says $lob IS an OCI-Lob
$lob is: OCI-Lob

Actual result:
--------------
instanceof says $lob is NOT an OCI-Lob!
is_a says $lob IS an OCI-Lob
$lob is: OCI-Lob