Email validation is rejecting valid email pattern

I stumbled on this bug while trying to register on a website which uses this framework. I got annoyed that I couldn't use the plus sign in my email and I traced back the problem to a RegExp being too specific in this framework. I made a small modification so that plus sign and underscore are now accepted in email. While the RegExp used is still not RFC compliant, it's at least a step forward in accepting more valid email. 

On a side note, you might want to consider using a RegExp that is too broad (ex.: /^\S+@\S+\.\S+$/) instead of too restrictive. It may let invalid email slip through, but it will at least not block valid email.