Different gcc versions

I have both gcc-3.4 and gcc-4.0(.1) installed on my system 
(debian-amd64 unstable), with links /usr/bin/gcc, g77, etc. to
the 3.4 versions. When I build R, the 3.4 version is picked up, 
which is fine.

However, when I 'install.packages("xyz")', R uses gcc-4.0 and
gfortran-4.0! Should I accept this or do something about it?
And if so, what? Of course, removing all 4.0 versions would 
help, but what if I don't want to do that?

 > version
         _
platform x86_64-unknown-linux-gnu
arch     x86_64
os       linux-gnu
system   x86_64, linux-gnu
status
major    2
minor    1.1
year     2005
month    06
day      20
language R

G?ran Brostr?m                    tel: +46 90 786 5223
Department of Statistics          fax: +46 90 786 6614
Ume? University                   http://www.stat.umu.se/~goran.brostrom/
SE-90187 Ume?, Sweden             e-mail: gb at stat.umu.se