R devel - Oct 2008 - beta symbol cut off in y axis label using jpeg/png/tiff

I am having trouble showing the Greek symbol "beta" correctly
in the y-axis label of bitmap plots.

Specifically, on my system the top of the "beta" symbol is cut off
using the following example:

file.jpg <- paste(tempfile(), ".jpg", sep = "")

jpeg(file.jpg, h = 3, w = 3, units = "in", res = 300, type =
"Xlib")
boxplot(rnorm(10), ylab = expression(beta))
dev.off()

I have the same problem with tiff() and png(). I don't have cairo
capabilities on this system.

On another system with cairo, if I use 'type = "cairo"' the
jpeg is
correct. If I use 'type = "Xlib", I get this error:

Error in title(ylab = expression(beta)) :
  X11 font -adobe-helvetica-%s-%s-*-*-%d-*-*-*-*-*-*-*, face 5 at size
12 could not be loaded

My system information is below.
----------------------

platform       sparc-sun-solaris2.10
arch           sparc
os             solaris2.10
system         sparc, solaris2.10
status
major          2
minor          7.1
year           2008
month          06
day            23
svn rev        45970
language       R
version.string R version 2.7.1 (2008-06-23)

sessionInfo:

R version 2.7.1 (2008-06-23)
sparc-sun-solaris2.10

locale:
C

attached base packages:
[1] grDevices datasets  splines   graphics  utils     stats     methods
[8] base

Capabilities:
    jpeg      png    tcltk      X11     aqua
    TRUE     TRUE     TRUE     TRUE    FALSE
http/ftp  sockets   libxml     fifo   cledit
    TRUE     TRUE     TRUE     TRUE     TRUE
   iconv      NLS  profmem    cairo
    TRUE     TRUE    FALSE    FALSE