[R] use of NULL environment is deprecated?

[Patrick Connolly]

]> version
               _                         
platform       x86_64-unknown-linux-gnu  
arch           x86_64                    
os             linux-gnu                 
system         x86_64, linux-gnu         
status                                   
major          2                         
minor          3.1                       
year           2006                      
month          06                        
day            01                        
svn rev        38247                     
language       R                         
version.string Version 2.3.1 (2006-06-01)


I see in the NEWS file the line:
    o	Use of NULL as an environment is deprecated and gives a warning.

Which duly happens.  I get warnings like this:
> Warning message:
use of NULL environment is deprecated

My problem is that I don't know what is being referred to.  A little
birdie tells me that in later versions of R, those warnings will
become errors so I need to work out where they're coming from before I
can use later versions.

My question is: How does one work out which is being referred to by
such a message?  The traceback() function is useful when failure
occurs.  Is there an analagous way of looking into warnings?

TIA

-- 
~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.   
   ___    Patrick Connolly   
 {~._.~}          		 Great minds discuss ideas    
 _( Y )_  	  	        Middle minds discuss events 
(:_~*~_:) 	       		 Small minds discuss people  
 (_)-(_)  	                           ..... Anon
	  
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