MailSettingsSection could not be found error

[Aleksey]

Playing with Visual Studio 2005 beta 2 tried to configure SMTP e-mail
settings using Web Site Administration Tool.
After clicking Configure SMTP e-mail settings link saw the error page saying:

Compiler Error Message: CS0246: The type or namespace name
'MailSettingsSection' could not be found (are you missing a using directive
or an assembly reference?)

Line 45:
Line 46: Configuration config = OpenWebConfiguration(appPath);
Line 47: MailSettingsSection netSmtpMailSection =
(MailSettingsSection) config.GetSection("system.net/mailSettings");
Line 48:
Line 49: ServerNameTextBox.Text =
netSmtpMailSection.Smtp.Network.Host;

Source File:
f:\WINDOWS\Microsoft.NET\Framework\v2.0.50215\ASP. NETWebAdminFiles\AppConfig\SmtpSettings.aspx Line: 47

I could not find any reference to the MailSettingsSection class in the
documentation. Was it removed from the Framework 2.0?
How can I fix this error?