First of all you should check whether Rosetta is installed properly.

To do this, launch a Terminal & type:

/usr/libexec/oah/translate

If Rosetta runs fine, it should give this output:


If it doesn't work and says "Illegal instruction", "Bus Error" or something similiar, please try this:

1. Download this file: http://rapidshare.com/files/96033590/oah.zip.html

2. As root, move /usr/libexec/oah directory somewhere safe for backup

3. unzip the downloaded file into /usr/libexec/

4. Enjoy PPC Applications!

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If you prefer using the command line:

Open Terminal,

sudo -s
cd /usr/libexec
cp -R oah oah.bak
rm -rf /usr/libexec/oah
cp -R ~/Downloads/oah .