modal popup extender return value for next sub

hi,

I finally made (with some help by some people here) a working modal popup extender popup.

I want this to replace my modal messageboxes in an web application, now this is my new probem:

showPopup("Delete User", "Please confirm the deletion of user " & id & "(" & GV_users.Rows(row).Cells(1).Text & ")", True)

If ('<something>' = True) Then
                        If (sql_prepareDeleteUser(GV_users.Rows(row).Cells(0).Text)) Then

I would like that the function showpopup returns a value based on the button clicked,,, just like a real msgbox with vbyes vbno.

is that somehow possible?

I read somewhere something related to an event with a parameter, but I don't know how to wait for that event and then take it's value.