How to use colored cursors?

[Jean-Christophe Dubacq <jean-christophe.dubacq@ens-lyon.org>]

Since I switched from xfree-4.3.0-ds4, I do not have the colored cursors
any more (I use experimental packages instead).

I do have a ~/.icons/default/index.theme:
[Icon Theme]
Inherits=whiteglass

I have the whiteglass files (locate whiteglass returns many results)

My XF86Config-4 uses HWCursor false:

Section "Device"
	Identifier	"Matrox G550"
	Driver		"mga"
	BusID		"PCI:1:0:0"
	Option		"HWCursor" "false"
	Option		"SWCursor" "true"
	Option "AGPMode" "4" 
EndSection

I even tried to add a few Xresources:
xrdb -query -all
*customization: -color
Xcursor.core:   false
Xcursor.size:   48
Xcursor.theme:  whiteglass
Xcursor.theme_core:     whiteglass
Xft.antialias:  1
Xft.dpi:        100,000000
Xft.hinting:    1
Xft.hintstyle:  hintmedium
Xft.rgba:       rgb

Nothing. I get the standard black with white border cursor.

Any hint?