2.6, 3.0, and truly independent intepreters

["Martin v. Löwis"]

> You seem confused.  PEP 3121 is for isolated interpreters (ie emulated
> processes), not threading.

Just a small remark: this wasn't the primary objective of the PEP.
The primary objective was to support module cleanup in a reliable
manner, to allow eventually to get modules garbage-collected properly.
However, I also kept the isolated interpreters feature in mind there.

Regards,
Martin