I attach an ebuild for fixing it. Thanks
Created attachment 105490 [details] mahjongg3d-0.96-r1.ebuild
I simply add: newicon bin/layouts/chinese_wall.bmp ${PN}.bmp make_desktop_entry mahjongg3d "Mahjongg 3D" /usr/share/pixmaps/${PN}.bmp Thanks
in portage. thanks for the bug report and patch.