[R] lattice: clipping data, not plot margins

[Dan Bebber]

I am plotting subsets of my data, using ylim.
This works fine, but the outer margin line widths of the plot are thin, due 
to clipping.
If I include
> trellis.par.set(clip=list(panel = "off"))
then the outer margin line widths are fine, but the outlying data is 
visible.

Is there any way of achieving both correct margin line widths and clipping 
of outlying data?

Thanks,
Dan Bebber

info: Windows XP, R 2.4.1., lattice 0.14-16