Joomla by default operates email cloaking - this is where an email address is replaced in the source code by Javascript.

Javascript is used to hide the actual email address from a bot but still displaying the email address on the front end to the web site user.

With email cloaking it is important to be aware -

1. Its not perfect in its ability to stop email being harvested by bots
2. Using an email (and its javascript) in an extension or component that is already using Javascript can cause the extension to fail or display wrongly.

If you run into issue number two - try this extension www.nonumber.nl/extensions/emailprotector

For more information about email cloaking - check out
docs.joomla.org/How_to_cloak_email_addresses

I believe there is an issue with email cloaking currently as of 10-11-14 so if problems arise with the current joomla version 3.3.6 I would look at the nonumber extension