CSIRO's Software Architectures and Component Technologies group have
published a detailed, rigorous and technical evaluation of 6 leading J2EE
application servers. The evaluation is both qualitative in terms of feature
comparisons, and quantitative in terms of assessing performance and
scalability through 'level playing field' testing.

A summary of the report can be found at:


http://www.cmis.csiro.au/adsat/

Regards,

Paul.