title: facet_grid problem : input string 1 is invalid in this locale?
body: <p>I am trying to create facet grid with the following code</p>
  
  <pre><code>p &lt;- ggplot(melted,aes(factor(country))) + geom_bar() +opts(axis.text.x =   theme_text(angle = 90,hjust = 1)) 
  
  p + facet_grid(. ~ provider)
  </code></pre>
  
  <p>but I always get the following error:</p>
  
  <p>Error in sub("^[^:]+: ([^\n]+)\n[0-9]+:(.*)$", "\1\2", expr) : 
     input string 1 is invalid in this locale</p>
  
  <p>I do not have any idea what I am doing wrong. also tried to factor my facet, which doesn't work either.</p>
  
  <p>Thx in advance!</p>