Chris,
Version 2.6.3 is for Eclipse 2.1.1. It’s version 3.6.3 that is for Eclipse 3.0M4. The common view of Eclipse M-builds are as a work in progress. They are great for allowing users to experiment with new features early in development but lack the completeness and stability of their eventual GA release.
First impressions are everything so we limit public trial releases of MyEclipse to those versions based on Eclipse GA releases, (ver 2.1.0 & 2.1.1). As a benefit to MyEclipse paid subscribers we also offer early access to MyEclipse 3.0M-build releases. I encourage you to reevaluating MyEclipse on the Eclipse 2.1.1 platform if possible. If you absolutely require MyEclipse on the Eclipse 3.0Mx platform consider upgrading your subscription for early access privileges. If you are not satisfied you can always cancel your subscription with our money back guarantee.
–Scott
MyEclipse Support