R help - Jun 2006 - Tcl/Tk failing in JGR, but not in R for Mac OS X GUI

Dear r-helpers,

I wonder if you can figure out why the following is working:

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

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

other attached packages:
igraph
"0.1.2"

 > g <- graph.ring(10)
 > tkplot(g)
Loading required package: tcltk
Loading Tcl/Tk interface ... done
[1] 1
********************************************************************
An X window appears, and the graph can be interactively manipulated,  
as intended. But in JGR:

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

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

other attached packages:
igraph    BHH2     JGR  JavaGD   rJava
"0.1.2" "0.2-1" "1.4-2" "0.3-3"
"0.4-3"

 > g <- graph.ring(10)
 > tkplot(g)
Loading required package: tcltk
Loading Tcl/Tk interface ... Error in fun(...) : Can't find a usable  
init.tcl in the following directories:
     @TCL_IN_FRAMEWORK@ @TCL_IN_FRAMEWORK@



This probably means that Tcl wasn't installed properly.
Error: .onLoad failed in 'loadNamespace' for 'tcltk'
Error in tkplot(g) : tcl/tk library not available
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_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
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