發問Eclipse 3.1 Plugin under Linux

I am trying to install TinyDT eclipse plugin under linux. This package dosesn't have standard install directory structure. It requires GEF plugin which I had installed. But I don't know where should I put this plugin into which directory. I have tried:
/usr/lib/eclipse/plugins, /usr/share/eclipse/plugins, and my local home directory. None of them makes Eclipse recognize my new plugin.

What could be wrong?

This plugin works under XP+Eclipse. There is no any install , just extract it into plugins.