tick marks in opposite axis xyplot

Hello,

I cannot find how to avoid drawing tick marks on the opposite side of axes
in xyplot (lattice package). Say you have a simple plot:

x <- y <- rnorm(10)
xyplot(y ~ x)

There are tick marks on the top and right axes. Is it possible to turn off
drawing of those tick marks, or even turn off drawing of those axes
completely? Thanks in advance.


Cheers,
Sebastian

Sebastian P. Luque