[BioC] Error loading tcltk for tkWidgets and widgetTools on duo Intel Mac under OS X

[Michael Parisi]

I recently got a duo Intel Mac OSX and loaded many Bioconductor packages 
that I had been using along with R 2.5.1.  All of the packages load and 
work except for tcltk, tkWidgets, ruuid, graph and GOstats.  I get the 
same error as posted previously about tcltk and tkWidgets (last on Sep 
19, 2006):

 >library(tcltk)
Loading Tcl/Tk interface ... Error in dyn.load(x, as.logical(local), 
as.logical(now)) :
    unable to load shared library 
'/Library/Frameworks/R.framework/Versions/2.5/Resources/library/tcltk/libs/i386/tcltk.so':
  
dlopen(/Library/Frameworks/R.framework/Versions/2.5/Resources/library/tcltk/libs/i386/tcltk.so, 
10): Library not loaded: /usr/X11R6/lib/libX11.6.dylib
  Referenced from: 
/Library/Frameworks/R.framework/Versions/2.5/Resources/library/tcltk/libs/i386/tcltk.so
  Reason: image not found
Error : .onLoad failed in 'loadNamespace' for 'tcltk'
Error: package/namespace load failed for 'tcltk'

Actually, loading ruuid gives me a slightly different message
 > library(ruuid)
Error in library(ruuid) : there is no package called 'ruuid'

However,  all of the packages I'm running into trouble with are indeed 
loaded and presumably in the correct place.  Any advice? 
 Thanks,  Michael.