XML Sitemap Generator – Stylesheet Issue

I am using XML Sitemap Generator for WordPress 3.1.0. I am using WP Version 2.5.1. My website is https://www.scsbend.com and my WordPress site is https://www.scsbend.com/blog. I have made the chmod 777 to the two sitemaps and have the sitemaps in the root directory.

The manual sitemap rebuild works without error. However when viewing the sitemap.xml it states:

The XML page cannot be displayed
Cannot view XML input using XSL style sheet. Please correct the error and then click the Refresh button, or try again later.

The following tags were not closed: stylesheet. Error processing resource ‘https://www.scsbend.com/sitemap.xml’.

____________
Google Webmaster Tools states:

Line Status Details
48 Parsing error
We were unable to read your Sitemap. It may contain an entry we are unable to recognize. Please validate your Sitemap before resubmitting. Found: May 27, 2008
48 Invalid XML tag
This tag was not recognized. Please fix it and resubmit. Parent tag:
Tag:
Found: urlset
changefreq
May 27, 2008
47 Invalid XML tag
This tag was not recognized. Please fix it and resubmit. Parent tag:
Tag:
Found: urlset
lastmod
May 27, 2008

Any suggestions? Thanks.