[R] package/namespace load failed for 'Rgraphviz'

[Michael Kubovy]

Dear R-helpers,

Can anyone tell me how to fix this:
 > library(Rgraphviz)
Loading required package: graph
Loading required package: Ruuid
Error in dyn.load(x, as.logical(local), as.logical(now)) :
	unable to load shared library '/Library/Frameworks/R.framework/ 
Resources/library/Rgraphviz/libs/ppc/Rgraphviz.so':
   dlopen(/Library/Frameworks/R.framework/Resources/library/Rgraphviz/ 
libs/ppc/Rgraphviz.so, 6): Library not loaded: /usr/local/lib/libpng. 
3.dylib
   Referenced from: /usr/local/lib/graphviz/libgvc.2.dylib
   Reason: image not found
Error: .onLoad failed in 'loadNamespace' for 'Rgraphviz'
Error: package/namespace load failed for 'Rgraphviz'

 > sessionInfo()
Version 2.3.1 (2006-06-01)
powerpc-apple-darwin8.6.0

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

other attached packages:
      graph      Ruuid    lattice       MASS        JGR      
JavaGD      rJava
   "1.10.6"   "1.10.0"  "0.13-10" "7.2-27.1"    "1.4-2"    "0.3-3"     
"0.4-3"
_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS:     P.O.Box 400400    Charlottesville, VA 22904-4400
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WWW:    http://www.people.virginia.edu/~mk9y/