'm having some problems with a WebControl, Sharepoint and
SessionState. and NullReferences.

Somewhere, this method it throwing a NullReference Exception.  It
began when I added the session information.

Options for null -
base - not likely - worked before SS added.

I think I handled the case of the empty session appropriately, if not
overzealously. Is there something funky about WSS and SessionState? Or
am I getting the SessionState from the wrong place?

Class Declaration:  public class WebQuizControl : WebControl

The Method:
protected override void CreateChildControls()
       {
           base.EnsureChildControls();
           if ( !isConfigured ) return;
           object temp = null;
           if (! HttpContext.Current.Session.IsNewSession)
               temp = HttpContext.Current.Session["questionSet"];

          // Does C# shortcut here? if temp == null is the castI
executed?
          if ( temp == null || ( temp as ExamCreator ) == null )
           {
               questionSet = new ExamCreator( Association, course,
module ); // parameters are valid
               HttpContext.Current.Session.Add( "questionSet",
questionSet );
           }
           else  // Probably not in here, as it crashes on initial
load.
           {
               questionSet =
HttpContext.Current.Session["questionSet"] as ExamCreator;
           }
           foreach ( Question q in questionSet.Questions )
           {
               this.Controls.Add( q );
           }

          // [snip] .. add submit, reset etc.
       }

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