Cannot Connect To A Named Instance Of SQL Server From Compact Framework 2.0

I have two instances of SQL Server on the same PC:

Default instance: SQL Server 2000
Named instance with name €œMS2005€?: SQL Server 2005.
Also I have another SQL Server 2005 on another PC.

I created a .NET 2.0 Compact Framework application that connects to the database and executes simple query. This application can connect to any instance of the SQL Server when it is executed on the PC (not on the server). But the problem is that when I try to execute the application from the windows CE 5.0 device, the application can only connect to the default instance (SQL 2000 and 2005) and can not connect to the named instance (Name: MS2005).
Is it some kind of limitation of the SqlClient library for the compact framework?

Below are the code and connection strings:

string connectionString = €œServer=1.1.1.1;Database=DB1;Uid=sa;Pwd=€?
string connectionString = €œServer=1.1.1.1\MS2005;Database=DB1;Uid=sa;Pwd=€?

using (SqlConnection connection = new SqlConnection(connectionString))
{
connection.Open(); //This is the point where exception is generated

using (SqlCommand command = connection.CreateCommand())
{
command.CommandText = "select count(*) from users";
object result = command.ExecuteScalar();

Console.WriteLine("Result: [{0}]", result);
}

connection.Close();
}


Thank you for your time and advice.