The installer and the requierd library were compiled using Java 1.5 which may result in errors when running metis under Java 1.4.

Solutions:

- upgrade to Java 1.5 (http://java.sun.com)
...)

- download the installer
"Metis_0.6a-install (JRE 1.4).jar", which has been tested using JRE 1.4.2 and should work for those not possible or wanting to upgade.