[R] How to change ${R_HOME}?

[tkobayas at indiana.edu]

Hi,

I am reinstalling R for Ubuntu Hardy using a CRAN mirror. I 
successfully installed R 2.6.2, but when I type 'R' in a terminal it 
says,

taquito at ubuntu:~$ R
.: 204: Can't open /usr/local/lib64/R/etc/ldpaths

And it seems like my R is at /usr/lib64/' not /usr/local/lib64. So I am 
thinking the file is pointing to a wrong directory so that R doesn't 
start up.

How to change the pointing R directory so that I can start R?

Thanks