Created attachment 163771 [details]
Email from the "Steps to reproduce", after doing a File -> "Save Message..."

Steps to reproduce:
* I received a plain-text automated email with a web link that I need to click to confirm an opt-in. (This email will be included as an attachment). [note: You can receive a similar email by going to http://www.retailmenot.com/view/linode.com , and entering an email address with a plus symbol in it, like "name+something@host.tld", in the "Email:" box, and clicking the "Monitor" button]
* After opening the email, I click on the link (or right-click on it, and choose "Open Link in Browser").
* The default browser (Firefox) attempts to open the link.

What happens:
* The URL-encoding in the email seems to be lost, as the browser opens this link: http://www.retailmenot.com/notify.php?action=c&email=nickpj+retailmenot@gmail.com&key=x5rxt
* This results in a page that says "Problem: Unable to confirm that request. Please check the url and try again."

Workaround:
* Right-click on the link in the email.
* Choose "Copy Link Location".
* Paste into the browser's address bar, and press enter.
* This opens this link, which has differs from the above URL in that it has URL encoding for the "+" and "@" symbols: http://www.retailmenot.com/notify.php?action=c&email=nickpj%2Bretailmenot%40gmail.com&key=x5rxt
* This results in a web page that says "Success! You will now receive email notifications."

Notes / other info:
* I also receive automated HTML-email notifications from another separate site, and they have behave the same (click doesn't work, but copy link does), and so I suspect the same issue. (i.e. it's more than one site, and it doesn't matter if it's an HTML-formatted-email or a plain-text email).
* Evo version is 2.28.1
* If I read the email through gmail's web interface and click the link, it opens okay. (i.e. suspect that the link itself is okay).
* There are a number of bits of software involved here, so I cannot be sure if this is a Evolution or a Firefox or a Gnome or a distro issue. My initial guess is Evolution, so I have filed it here (but if this seems wrong then please let me know, and I will move it to the right place).