Changing graphic titles when using bquote and resizing the graphic window

Dear list,

I found a strange behavior of the graphic display when using bquote to set a title to a plot. The problem arise when you manually resize the graphic window using the mouse. It happens on both quartz and x11 devices. Here's a reproducible example:

par(mfrow = c(1,3))
for (i in 1:3){
   title<- as.expression(bquote(gamma[.(i)]))
   plot(1:10, main = title)
}

Once you ran the code, the figure displays as expected --- each title is $\gamma_i$, $i=1, 2, 3$. Now if you resize manually the graphic window using the mouse all the titles will be set to $\gamma_3$.

In case this is useful, here's the ouput of sessionInfo().

sessionInfo()

R version 2.14.0 (2011-10-31)
Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit)

locale:
[1] C

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

Best,
Mathieu

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