Unable to create directory?

I have tried to install the pls.pcr package, but as a install newbie, I
wasn't too successful. I tried the command
"install.package("pls.pcr",lib="~/lib/R/",CRAN="http://mirrors.sunsite.dk/cran").
The download seemed to run smoothly, but in the end I got the response
"ERROR: cannot write to or create directory '~/lib/R'"

Before I try to get my sysadmins to work on this, is it a non-R
problem (i e something wrong with directory premissions) or is it
some R detail I've missed? Hints anyone?

(I run R in a Unix environment: a SunRay/Solaris combination.)

--robert