For those of you that are wondering why unrevoked3 doesn't work on the Eris
This works for stock 2.1 finally!
Got it form xda-developers. Thanks goes to them!

Click thanks to see the link & download the Files and extract them to a folder named erisroot on your C:\ drive.
then open command prompt and cd to it like this:

cd \erisroot\

then type in the commands provided in the instructions.
be sure to flash the zip file included thru recovery menu after you've entered all the commands.

ENJOY!

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