How do you configure trust levels to support membership in VS 2005?

[nedk]

I did the walkthrough at
http://msdn2.microsoft.com/library/879kf95c(en-us,vs.80).aspx on
creating a web site with membership and user login in VS 2005 but when
I click on the login button I'm getting an error that says the feature
is not supported at the configured trust level. Does anyone have a
solution for this. I'm not finding anything on the web. thanks.

Server Error in '/testweb' Application.
--------------------------------------------------------------------------------

This feature is not supported at the configured trust level.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: This feature is not
supported at the configured trust level.

Source Error:

An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.


Stack Trace:


[HttpException (0x80004005): This feature is not supported at the
configured trust level.]
System.Web.Security.Membership.Initialize() +222
System.Web.UI.WebControls.LoginUtil.GetProvider(String providerName)
+32
System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs
e) +130
System.Web.UI.WebControls.Login.AttemptLogin() +94
System.Web.UI.WebControls.Login.OnBubbleEvent(Object source,
EventArgs e) +101
System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs
args) +35
System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +115
System.Web.UI.WebControls.Button.RaisePostBackEvent(String
eventArgument) +134

System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String
eventArgument) +7
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler
sourceControl, String eventArgument) +11
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
+33
System.Web.UI.Page.ProcessRequestMain(Boolean
includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
+5670