assertEquals() equates NULL and empty values

The assertEquals method in PHPUnit_Extensions_Database_DataSet_ReplacementTable and PHPUnit_Extensions_Database_DataSet_AbstractTable performs a not equal != comparison between $this->getValue($i, $columnName) and $other->getValue($i, $columnName). This leads to NULL and empty character fields, or int(0), being considered equivalent. Performing a not identical comparison !== here differentiates NULL from other values.