R help - Apr 2009 - Problem with greek "beta" symbol in plot using CairoPDF (Windows)

Dear R-Helpers,

I have a problem with displaying the greek "beta" symbol in PDF files 
using Cairo library - it displays as an empty box. The same also happens 
for a dash symbol in subscript. Both symbols are displayed correctly if 
the plot is produced on screen (outside of CairoPDF).

The syntax that I use for it in plot command is: 
'xlab=expression(paste("A",beta,)[1-42])'.

When I try to select a different font family using 'family' option in 
the CairoPDF command - it has no effect. I tried 'CairoFonts', but it 
displays an error:

'Warning message:
In CairoFonts() :
   the R Cairo package was not installed with fontconfig. Please 
consider installing the cairo graphics engine (www.cairographics.org) 
with freetype and fontconfig support'

I have the most recent GTK+ installed. I don't know where to look for 
solution. Anyone able to help?

Here is my session info:

 > sessionInfo()
R version 2.8.1 (2008-12-22)
i386-pc-mingw32

locale:
LC_COLLATE=Polish_Poland.1250;LC_CTYPE=Polish_Poland.1250;LC_MONETARY=Polish_Poland.1250;LC_NUMERIC=C;LC_TIME=Polish_Poland.1250

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

other attached packages:
[1] Cairo_1.4-5
 >


-- 
Michal J. Figurski
HUP, Pathology & Laboratory Medicine
Biomarker Research Laboratory
Philadelphia, USA