Java and Software Lifecycle Management

We are about to develop our first Java-applications. At the moment, we are 
thinking about the best way to set up a Software Lifecycle Management 
method. We want to store the Java-sources and Java-classes on a file 
server, so each of the developers will have access to the latest versions 
of the sources. Furthermore, we want to have different environments for 
Development, Testing, Integration Testing and Production. We wonder how 
things can be arranged in an efficient, easy-to-use and yet robust way. I 
would appreciate it if anybody could give some advice.

I know a little about CVS, but I do not fully understand the role of CVS 
in an overall Software Lifecycle Management setup. Any clarification would 
be appreciated. 

I also would like to know what is the most common 'level of management'. 
Should sources and classes be managed on an individual basis, or is it 
more appropriate to use Jar-files as the 'level of management'? In the 
latter case, I am afraid that there will often be conflicts when classes 
within a Jar-file are maintained for different reasons. A change that was 
made for a particular project might already be ready to be moved to a test 
environment, while another class in the Jar-file is still under 
maintenance. How are such situations normally handled?

Thanks,

Ewout