[R-sig-Geo] Adehabitat crashed R on MacOS 2.15.2

[Els Ducheyne]

Dear list
I am trying to run ENFA for presence only records. I have installed adehabitat v1.18.11 on R2.15.2 on MacOS 10.8.2. I
Whilst the library is successfully installed and loaded, it crashed R when I am trying to run other commands after loading the library.
Did anyone experience this before? 
Is it the Tcl/Tk that causes the problem, could I load the package without the Tcl/Tk?
I have tested under windows too with same version of adehabitat and R and there it works fine. Unfortunately, I will use the package for teaching and some students use MacOS so therefore I would like to find a solution.

>sessionInfo()
R version 2.15.2 (2012-10-26)
Platform: i386-apple-darwin9.8.0/i386 (32 bit)

locale
[1] en_GB.UTF-8/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8

attached base packages:
stats graphics grDevices utils datasets methods base
> library(adehabitat)
Loading required package: ade4
Attaching package: 'ade4'
The following objects are masked from 'package:base'
within
loading required package:tkrplot
loading required package: tcltk
Loading Tcl/Tk interface
> sessionInfo()

After the second sessionInfo() R does not respond, nor with any other command. The only option is Force quit and reboot.

Thanks for any help
Els