I got quite confused why the revolution mail client often pops up when I press right key on a link.
To solve this, I have to click on a blank space of the page, or scroll the middle key of the mouse.
But this is really inconvenient.
Any one got the same problem? And how did you solve it?
I think that this is actually a feature. Mouse gestures probably. But honestly, I have to agree with you. I find these mouse gestures annoying and inconvenient too. There were a lot of times that I simply wanted to right-click on a link but the "e-mail client chooser" pop-ups. In your case, Evolution might have been already configured as the default that's why it's the one that opens. However, I believe that there's a way of turning them off, as far as I can remember.
Which linux distribution?
Also, Firefox doesn't have mouse gestures installed by default so something odd is going on here.
Perhaps ensure you only have sensible extensions (add-ons) installed and have a look in "about:config" (type it into the address bar) and see if there's any settings which look like they might help?