When did Gibson begin using the Plek machine?

[jazzrat]

Just got an '07 ES-339. It plays fine but certainly not the quality fretwork of my Ibanez AS103.
The tone is worth the price of admission but I am wondering.....

 

[Sean French]

'06

 

[whitehall]

I believe 06 on the custom shop models and 08 on the Gibson USA ones.