This is very interesting. Eclipse 3.0 is going to run 2.1 plugins with out any modification.
One of the interesting things that came out of the EclipseCon conference was that
the developers have completely reversed their earlier decision to have 3.0 introduce
breaking changes. Almost all 2.1 plug-ins are now supposed to run unmodified in their
binary forms in 3.0. This is done through some very clever slight of hand in the 3.0
run-time that allows you, for example, to call methods that don't actually exist anymore
in the normally visible versions of their classes. Any 2.1 plug-in that doesn't run
in 3.0 starting with M7 (out later this week) should be reported as a bug.
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