StateMachineWorkflowInstance.PossibleStateTransistions returns incorrect result

Question

Hi,

I have a windows workflow state machine that was working okay. To inform the user of their possible options when working with the workflow I call StateMachineWorkflowInstance.PossibleStateTransistions which would return all the possible transitions. I then added a StateInitializationActivity to each of the states. Now when I call StateMachineWorkflowInstance.PossibleStateTransistions only some of the transitions are returned.

Any ideas on what might cause this behavior?

Edit: It is not just that I added a StateInitializationActivity, but within the StateInitializationActivity I have a custom Activity to initialize the state. If I change this custom activity to a codeActivity and do the initialization there, then .PossibleStateTranisitions works correctly. This is what my custom activity looks like

using System;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Workflow.ComponentModel;

using GroupBookingCommon;

namespace GroupBookingWorkflows
{
    public class InitializeGroupBookingActivity: Activity
    {
 public static DependencyProperty GroupBookingProperty =    System.Workflow.ComponentModel.DependencyProperty.Register("GroupBooking", typeof(GroupBooking), typeof(InitializeGroupBookingActivity));
     public GroupBooking GroupBooking
     {
      get { return ((GroupBooking)(base.GetValue(InitializeGroupBookingActivity.GroupBookingProperty))); }
      set { base.SetValue(InitializeGroupBookingActivity.GroupBookingProperty, value); }
     }

     public static DependencyProperty TimeUntilDueProperty = System.Workflow.ComponentModel.DependencyProperty.Register("TimeUntilDue", typeof(TimeSpan), typeof(InitializeGroupBookingActivity));
     public TimeSpan TimeUntilDue
     {
      get { return ((TimeSpan)(base.GetValue(InitializeGroupBookingActivity.TimeUntilDueProperty))); }
      set { base.SetValue(InitializeGroupBookingActivity.TimeUntilDueProperty, value); }
     }

     public static DependencyProperty DueDateMeasuredFromProperty = DependencyProperty.Register("DueDateMeasuredFrom", typeof(String), typeof(InitializeGroupBookingActivity));
     public String DueDateMeasuredFrom
      {
      get { return ((String)(base.GetValue(InitializeGroupBookingActivity.DueDateMeasuredFromProperty)));}
      set { base.SetValue(InitializeGroupBookingActivity.DueDateMeasuredFromProperty, value); }
     }

     protected override ActivityExecutionStatus Execute(ActivityExecutionContext executionContext)
     {
      if (GroupBooking != null)
      {
       if (TimeUntilDue.TotalDays != 0)
        {
         if (DueDateMeasuredFrom == "BookingDate")
          GroupBooking.NextDueDate = GroupBooking.BookingDate.Add(TimeUntilDue);
        else
          GroupBooking.NextDueDate = (GroupBooking.Departure.Add(TimeUntilDue) > DateTime.Now.Date) ? GroupBooking.Departure.Add(TimeUntilDue) : DateTime.Now;
        }

        IGroupBookingTransactionService txnService = executionContext.GetService<IGroupBookingTransactionService>();
         txnService.UpdateGroupBooking(GroupBooking);
        }
        return ActivityExecutionStatus.Executing;
     }
    }
}