[Plugin: Google XML Sitemaps] Strange LastChanged date assigned to blog url

i installed the plugin, updated the settings and created the sitemap. everything seems good except the date associated with the homepage url is strange.

the blog was only recently created and most of the dates of all the posts and pages will be similar to this example, 2010-11-17 16:37, but the date associated with the homepage is 1999-11-30 00:00.

Not sure what effect this will have if any but is there a way i can modify the date so its a recent date?