invalid date error

I am getting an invalid date error on a line in my Google sitemap:
Invalid date (Line 9726)

The line in question is <lastmod></lastmod> below

<url>
<loc>http://www.betterlifemedia.com/shop.do?pID=117</loc>
<lastmod>2005-12-11T22:03:32+00:00</lastmod>
<priority>0.04</priority>
<changefreq>monthly</changefreq>
</url>

I checked it with the example in the docs: 2004-09-22T14:12:14+00:00

Can't seem to see what is wrong with the date ...