FVWM: Center the window with the delay

[Bob Marcan]

Hi.
Fedora20, fvwm-2.6.5-6.fc20.x86_64

Style "*SMPlayer*"  PositionPlacement Center

When the smplayer is started, final geometry is not yet defined,
it depends on the geometry of the video.
How to center this window with some delay?
TIA, Bob