difference between activation energy and threshold energy?

Hi.

I was wondering whether any of you know what's the difference between activation energy and threshold energy?

According to trusty old WikiAnswers, there's no difference. This is in accordance with a couple of other websites.

But according to my textbook:

Activation energy is the minimum increase in potential energy of a system required for molecules to react.

-and-

Threshold energy is the mimum kinetic energy required to convert kinetic energy into activation energy during the formation of the activated complex.

Aren't these the same things?  :-\ ??? :-X

Yes, they are in fact the same thing