In the class "ezemailtype.php" there might be an error in :

function validateObjectAttributeHTTPInput( $http, $base, $contentObjectAttribute )

The following statement on line 81

$classAttribute = $contentObjectAttribute->contentClassAttribute();

should be placed before the "if" line 78,

otherwise $classAttribute is not initialized when passing in the "else if" line 102 (giving then a PHP error)

Hakim