First set the variable CVSROOT to /class/`username`/cvsroot
[Or any other directory you wish]
[For csh/tcsh: setenv CVSROOT ~/cvsroot]
[For bash/ksh: CVSROOT=~/cvsroot;export CVSROOT]
Next run cvsinit. It will create this directory along with the
subdirectory CVSROOT and put several files into CVSROOT.