Sitemap tag error

hello, I have submitted my sitemap in google webmaster tool and it give me this error

Hello,

what do you have on line 22 in that sitemap file?

i'm little confuse, I have 2 sitemaps, 1st links to the 2nd:

Code:

<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex
      xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="
            http://www.sitemaps.org/schemas/sitemap/0.9
            http://www.sitemaps.org/schemas/sitemap/09/siteindex.xsd">
<sitemap>
	<loc>http://mozymac.com/forums/sitemap_1.xml.gz</loc>
	<lastmod>2009-06-22T03:19:40+00:00</lastmod>
</sitemap>

</sitemapindex>

2nd is:

Code:

<?xml version="1.0" encoding="UTF-8"?>
<urlset
      xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="
            http://www.sitemaps.org/schemas/sitemap/0.9
            http://www.sitemaps.org/schemas/sitemap/09/sitemap.xsd">
<url>
  <loc>http://mozymac.com/forums/</loc>
  <priority>1</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f4/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-16T10:19:17+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/</loc>
  <priority></priority>
  <lastmod>2009-06-16T10:19:17+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f6/</loc>
  <priority>0.1676</priority>
  <lastmod>2009-06-16T08:10:35+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f8/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f9/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-16T09:40:04+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f10/</loc>
  <priority>0.2235</priority>
  <lastmod>2009-06-16T09:40:04+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f11/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f12/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f13/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f14/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-20T16:54:38+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f15/</loc>
  <priority>0.2235</priority>
  <lastmod>2009-06-16T05:51:48+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f16/</loc>
  <priority>0.2235</priority>
  <lastmod>2009-06-20T16:54:38+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f17/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f18/</loc>
  <priority>0.2235</priority>
  <lastmod>2009-06-15T16:47:29+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f1/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f2/</loc>
  <priority>0.2235</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f3/</loc>
  <priority>0.2399</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>daily</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/switch-101-how-change-default-program-3/</loc>
  <priority>0.6215</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/how-go-through-windows-same-application-4/</loc>
  <priority>0.885</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/how-take-screenshot-mac-os-x-12/</loc>
  <priority>0.6215</priority>
  <lastmod>2009-06-16T10:19:17+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/switch-gains-losses-5/</loc>
  <priority>0.6215</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f5/important-keyboard-shortcuts-new-mac-users-7/</loc>
  <priority>0.6215</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f6/safari-how-make-links-open-new-tab-instead-new-window-6/</loc>
  <priority>0.495</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f6/how-add-url-contact-address-book-10/</loc>
  <priority>0.8815</priority>
  <lastmod>2009-06-16T08:10:35+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f10/how-password-protect-your-documents-iwork-09-a-11/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-16T09:40:04+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f15/installing-photoshop-cs4-mac-os-x-9/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-16T05:51:48+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f16/universal-alarms-application-13/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-20T16:54:38+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f18/unboxing-ipod-shuffle-3rd-gen-8/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-15T16:47:29+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/f2/mozymac-grad-opening-2/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-15T16:41:36+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
<url>
  <loc>http://mozymac.com/forums/tags/</loc>
  <priority>0.9</priority>
  <lastmod>2009-06-23T17:06:39+00:00</lastmod>
  <changefreq>weekly</changefreq>
</url>
</urlset>

this is line 22:

<priority></priority>

Please apply the following fix Google webmaster tools tells me these warnings , delete all your sitemap files and regenerate again.