Description:
------------
sybase_fetch_field is consistently returning me a NULL value for column_source.

Reproduce code:
---------------
$conn = @sybase_pconnect('server','user','pass');
$query = "SELECT * FROM Products WHERE productID = 1";
$rs = sybase_query($query);
$row = sybase_fetch_field($rs);

echo '<pre>';
print_r($row);
echo '</pre>';

Expected result:
----------------
stdClass Object
(
    [name] => productID
    [max_length] => 11
    [column_source] => 'Products'
    [numeric] => 1
    [type] => int
)

Actual result:
--------------
stdClass Object
(
    [name] => productID
    [max_length] => 11
    [column_source] => 
    [numeric] => 1
    [type] => int
)