1. A system for compiling Enterprise JavaBean (EJB) classes, comprising: a server, having a server version information associated therewith and executing a plurality of compiled EJB classes stored thereon; an ejb-jar file for storing the plurality of compiled EJB classes, together with, for each EJB class therein, a first snapshot of deployment related version information for that EJB class, wherein the first snapshot defines a deployment descriptor for the EJB class and the version of both the EJB class and the server, at the time that particular EJB class was compiled; and an EJB compiler that generates wrapper classes for each EJB class, including wherein the EJB compiler, following deployment of a previously compiled EJB class to a new version of the server, at a later point in time, automatically determines a second snapshot of deployment related version information for the new version of the server, and compares the first and second snapshots to determine whether the EJB compiler needs to be invoked again on the previously compiled EJB class, and if so automatically generates wrapper classes for use with the new version of the server.