This option may contain an email address to which notifications about page adds and changes will be sent. No emails are sent when this is a blank string. To add more than one email address, use the comma to separate the entries (','). (You can configure the “From” email address used for all mails sent through DokuWiki via the mailfrom setting.)
Note: this is probably only useful for very small wikis or in the very beginning of setting up a wiki. Once your wiki sees more frequent edits, Email Subscriptions will give you much better control over your email notifications.