Possible mac-specific bug in svg (cairo) graphics

I think you got the corresponding response to your post before -

Apologies: I didn't see that reponse.

cairographics cannot locate an italic version of the font -  
switching to a font which has the desired traits will produce the  
desired output, e.g.:

svg("test.svg", width=4,4,8)
par(family="Arial")
plot.new()
text(0.5,0.5,labels=expression(italic("This should be in italics")))
dev.off()

Thanks. I tried this with family="Arial", family="Times",  
family="serif", family="sans", family="Verdana", and family="mono",  
and they all come out as bold.

I guess if this doesn't happen on other systems, then is must be a  
problem with my R or system setup. Unfortunately I don't have another  
system  to try this out on.

The italic versions of Arial, Time, and Verdana are all available,  
according to Font Book.

Have you any suggestions as to how I could try and find out what is  
going on here? Can I activate some sort of debugging or verbose mode  
in Cairographics?

Cheers

Yan