[PD] Hide GEM window with a subpatch window

[Jack]

When i open a subpatch hiding completely the GEM window, pd freeze.
When this subpatch window hide 99,9 % of the GEM window there is no  
problem.
Any idea about this bug ?

Powerbook G4
MacOSX.4.11
pd 0.39.3-extended
GEM 0.91-cvs

++

Jack