This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
I too use "+" in my gmail e-mail for some things. Like directing e-mails to a newsletter folder. I was not aware that JForum didn't support it. Email address validation is the type of thing you take for granted is correct when you use open source software! I'll take a look at it. We have a deployment shortly so it will be deployed soon if it is simple.