Webstart uses a separate classloader system from standard java or from RCP, so any 3rd party libraries that use custom classloaders may have problems.

This affects JasperReports in that it uses it's own classloader to load, prepare, and display reports. Jasper seems to be compatible with RCP, OR compatible with Webstart, but not both.

A temporary, unpleasant solution was found that works by:
1. any report file should be compiled, and the resulting temporary java source file should be copied to the /src directory of the jasperreports plugins
2. I'm creating a net.sf.jasperreports.hack plugin which contains various ugly hacks to the jasperreports classloader so that it can load and process these reports despite the strange classloader issues

This works for now, but is not a correct solution (As well as adds an extra 15 megs to the maeviz download). A correct solution should be found, or an alternative to webstart, or an alternative to jasperreports should be found.