[R] mtrace() fails

[Norm Matloff]

I find the R debug package very useful.  I've installed and used it on
several of the machines I use, without problems, but on one machine I
get the following error:

   Loading required package: mvbutils
   Loading required package: utils
   MVBUTILS: no "tasks" vector found in ROOT
   Loading required package: tcltk
   Loading Tcl/Tk interface ... done
   [Previously saved workspace restored]
   
   > source("marbles.r")
   > mtrace(sim4)
   > sim4(100)
   Error in all.levs[[j]] : subscript out of bounds

Here's my setting:

   > sessionInfo()
   R version 2.5.0 (2007-04-23)
   i686-redhat-linux-gnu
   
   locale:
   LC_CTYPE=en_US.UTF-8;LC_NUMERIC=C;LC_TIME=en_US.UTF-8;LC_COLLATE=en_US.UTF-8;LC_MONETARY=en_US.UTF-8;LC_MESSAGES=en_US.UTF-8;LC_PAPER=en_US.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US.UTF-8;LC_IDENTIFICATION=C
   
   attached base packages:
   [1] "stats"     "graphics"  "grDevices" "datasets"  "tcltk"     "utils"
   [7] "methods"   "base"
   
   other attached packages:
      debug mvbutils
   "1.1.0"  "1.1.1"

Any suggestions anyone might have would be highly appreciated.

Norm Matloff