Access 2000: Updating SubForm Charts...need new event?

Experts,

This has been bugging me -

I made a form that displays all the employees, and a subform displays a chart that graphs where each employee's expenses are categorized.  To get the chart to update I had to set the Chart Query/DataSource to:

--------
SELECT Category, Sum([TransactionsQuery].Cost) AS SumOfCost, [TranactionsQuery].EmployeeID
FROM [TransactionsQuery]
WHERE ((([TransactionsQuery].EmployeeID)=[Forms]![frmEmployeeSpendCharts].[EmployeeID]))
GROUP BY [TransactionsQuery].Category, [TransactionsQuery].EmployeeID;
--------

The Where Clause was my favorite part...

The next part to figure out was how to get the chart to update as I cycle through employees - so I searched on here and found that I could use the On Current Event for the Form, and it worked.  (love this site)

----
Private Sub Form_Current()
Forms(frmEmployeeSpendCharts).Refresh
End Sub
-------

But...

I put a button on the main form to open the frmEmployeeSpendCharts, and when the form updates I can cycle through the employees, but the chart does not update anymore.  Is this because the form opens Modal or something?  Is there another event I can use to make the chart update again again?  When I open the form just by double clicking on it in the Access window, it works fine....I think the problem lies in how the main form handles it:

-----------------------
Private Sub cmdOpenEmployeeSpendCharts_Click()
On Error GoTo Err_cmdOpenEmployeeSpendCharts_Click
    Dim stDocName As String
    Dim stLinkCriteria As String
    stDocName = "frmEmployeeSpendCharts"
    DoCmd.OpenForm stDocName, , , stLinkCriteria
Exit_cmdOpenEmployeeSpendCharts_Click:
    Exit Sub
Err_cmdOpenEmployeeSpendCharts_Click:
    MsgBox Err.Description
    Resume Exit_cmdOpenEmployeeSpendCharts_Click
End Sub
-----------------


-Jess

PS - I'm sure you'll need more info from me, so just ask and I'll respond...