Indsætter 28-06-1894 i SQL

Hvorfor indsætter nedenstående kode 28-06-1894 i tildato
Response.Write nydato viser fint nok 01-11-2003
tildato er et datetime felt.

<%
conn.Open strDSN
sql = "select * from bruger"
Set rs = conn.execute(sql)
Do While Not rs.EOF
nydato = DateAdd("d", 21, date)
Response.Write nydato
sqlup = "update bruger set tildato = " & nydato & " WHERE id = " & rs("id")
conn.execute(sqlup)
  rs.MoveNext
Loop

set rs = nothing
conn.close

%>