Antialias problem, It can be possible to set antialias = false for a widget?

[tonnot]

I have a custom widget which acts as a container. It has a custom paintevent to draw a rounden external rect.
(this is the dark grey example).
I have a Qframe with a convenient stylesheet to draw a rounded rect to the bottom left and bottom right corners. As you can see at the left green example, the rounden corners are showed right.
If I put this Qframe inside my customwidget, as you can see there is a strange paint at the corners, probably because the antialias work.( The right top green example )
Maybe it can be fixed if I could to cancel antialias for the Qframe? Is it possibble ?
Thanks