Reasons and advantages for upgrading to Java 6 for a non-technical decider (at the client)

Question

I\'d like to upgrade from Java 5 to Java 6. We all know about the technical advantages and benefits, but:

I have the problem that a major client refuses to upgrade f

Answer 1

From the source:

Q: How is Java SE 6 different from the previous version (J2SE 5.0): what are the improved and updated areas, such as functionality, security, performance?

A: Anyone who has existing Java applications, will benefit immediately from the performance, reliability, and UI improvements in Java SE 6. Coupled with the expanded monitoring and diagnositics capacities built into the platform, the release delivers dramatic out-of-the-box benefits without any coding changes or even a re-compile necessary. Simply running existing Java applications on this latest release is all that is needed.

More on the same matter (may be of help to elaborate more to the client):

Top 10 Reasons to Upgrade to Java 6

Why should I upgrade to Java 6?