Try display:inline; or display:inline-block in the anchor style attribute. Looks like a parent css rule is making the anchor tag a block element.
<div id="footer_design">
designed by: Joe Blogs   e-mail:<a href="mailto:lokismind@gmail.com" style="font-family:Arial;font-size:16px;display:inline;">joeblogs@gmail.com</a>
</div>