Eclipse plugins are extremely cool, but the way they're being configured in Ganymede (Eclipse 3.4) is awful and makes transferring your configuration to another environment almost impossible. The new software update doesn't allow you to specify different install locations for the plugins. Ganymede also includes the "Classic Update", but in most of the installations it's not available. Some have reported that in the Eclipse Classic it can be set through Window -> Preferences -> General -> Capabilities. If that is not your case, please follow, cause I'll explain to you how to enable the classic update.
In reality that is quite simple, just browse to
WORKSPACE/.metadata/.plugins/org.eclipse.core.runtime/.settings/org.eclipse.ui.workbench.prefs and add a new line containing:
That's it, now you have both the new and classic updates available.
I use the classic update for installing plugins to a directory other than
eclipse/plugins. I've been installing for example JDT to
eclipse/3rdp/jdt folder. The advantage from this is that when a new plugin breaks your whole installation, removing it is a bit easier. Also transferring the installation to another computer or a different Eclipse version should be easier.
Hope you find this useful!