[R] Problem with graphics device in Mac OS X

[WAYNE KING]

Hello List,
   I am teaching a basic course where students are encouraged to use R. There are a few students using Mac OS X. As a test we downloaded and installed the latest .dmg file (R-2.6.1.dmg) onto a intel Mac running 10.5.1. A device query yields

> getOption("device")
"quartz"

But any plot command does not bring up a plot (e.g. plot(), boxplot(), hist()).

I found a thread concerning X11 windows under Mac OS X but I feel these users will most likely be just using the native quartz device.

Invoking a call to quartz() first does not seem to help, e.g.

>quartz()
>plot(rnorm(100,0,1))

produces no output and no error message (Nothing happens). A call to dev.cur() seems to indicate a device is active.
>quartz()
>dev.cur()
quartz
2

but again a plot command produces no figure. Sorry am I not a Mac OS user and I did check the archives but found mostly discussions on X11() under Mac OS X. 

Wayne