You could do

Private Sub Button_Click()
   Shell "javaw -classpath {program home dir} package.classLoader,
vbNormalFocus
End Sub

and use the Windows API to handle the program (the value return by Shell has
something to do with the program status), or there might even be such
function in VB, but it's been too long since I've touch that language :)
look that UP in MSDN.

-Yanick