[R] Histogram messed up

[Berry Boessenkool]

Hey all,

I encountered a problem drawing a histogram.
You can view the picture here:
http://dl.dropbox.com/u/4836866/Bad_Histogramm.png


What happens:
the bars are drawn with different starting points, thus no straight zero-line is there.
And bars are overlapping. (or sometimes apart from each other.)


How it happens:
hist(volcano, breaks=10) # and any other data
This also happens with barplot(rnorm(10,10,1), space=0).
resizing the graphics window shows the double line in differing places.


What I thought may cause it:
Just installed "xlsReadWrite", but I don't think that should be a problem, even though it's kind of irregular, with the xls.getshlib().
I restarted R when I noticed this, but even without lybrarying the package, it still happens.
I only recently upgraded to R 2.13.1, so I'm not sure it didn't happen before the package.
It did not happen with older R versions, that I do know. But that isn't necessarily causal.


What I want to know:
Any idea what may be causing this? Or better yet, what may be solving this?
Am I the only one with the problem? Could it be a bug? Is it my computer?

Any help would be highly appreciated!


What you may need to know:
Im using R on a Windows XP machine.
here's my
> sessionInfo()
R version 2.13.1 (2011-07-08)
Platform: i386-pc-mingw32/i386 (32-bit)

locale:
[1] LC_COLLATE=German_Germany.1252  LC_CTYPE=German_Germany.1252    LC_MONETARY=German_Germany.1252
[4] LC_NUMERIC=C                    LC_TIME=German_Germany.1252    

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


-------------------------------------
Berry Boessenkool
D-14476 Potsdam
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