SmartCVS is a commercial cross-platform CVS application written in Java. It is the best CVS client I've found for Linux. I use it, even though it's a commercial product, because I need a good CVS client in order to get work done. You can download SmartCVS from http://www.syntevo.com/smartcvs/.
You'll need a fairly recent version of the Sun JRE, so install that first.
Download the generic SmartCVS archive for Linux.
Move to the directory where you would like to install it, such as /etc.
cd /etc
Extract the file.
sudo tar xvf /<path>/smartcvs-generic-<version>.tar.gz
Change to the bin directory.
cd smartcvs-<version>/bin
Edit the smartcvs.sh file
sudo vim smartcvs.sh
Change the JAVA_HOME line to point to your Sun JRE directory.
JAVA_HOME=/etc/jre1.6.0_03/
Optionally, create a symbolic link to smartcvs.sh in /usr/bin.
ln -s /etc/smartcvs-<version>/bin/smartcvs.sh /usr/bin/smartcvs
Now, you can just execute smartcvs or the smartcvs.sh file.