Field Type Nvarchar

i have a simple table with a field called "authors". this filed have a nvarchar(max) type (in MSSql 2005). i have a simple query "Select authors FROM table". in query analizer this return the value of authors, but when i run this in asp page, the field is empty.

in the code i have:

Set rs = Server.CreateObject("ADODB.Recordset")
rs.Open sql, Conn, 1, 1

but rs("Authors") is empty.

If i change the type (and i use nvarchar(4000) for authors) there is no problem. for the connection i have Driver={SQL Native Client}.