The thread Anup mentioned describes what needs to be done; to change the regular expression, go to Admin -> Database -> Customize Tables -> Demographics, and click on the 'dgraph_email' column. By default this has a "Form Regex" value of: ^[\w.-]+\@[\w.-]+\.[\w.-]+$ To change this to what you're looking for, you'll probably want to change this last part: ^[\w.-]+\@[\w.-]+\.
[\w.-]+$ to 'org', so that the whole thing looks like: ^[\w.-]+\@[\w.-]+\.
org$. If you then decided you also wanted to allow .edu and .gov signups, for example, you could use: ^[\w.-]+\@[\w.-]+\.
(org|edu|gov)$
Jason Rhinelander
Gossamer Threads jason@gossamer-threads.com