I've heard there is a way to do that, but the website (that i can't remember) said it could crash your lightroom. With that i didn't want to try it. But i did find an add-on to lightroom that will do that along with add borders to you prints.
http://www.timothyarmes.com/lrmogrify.php
it's a free download if you don't mind keeping the export to 10 or less. i gave them $5 to get the unrestricted version.
Don't forget the Imagemagick program that is free to.
http://www.imagemagick.org/script/bi...es.php#windows
Here's one of my pictures exported from lightroom ver 1 something..

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