Forum Sitemap - Missing XML tag

[محروم.كوم]

Hi Gang, I get an error from Google webmaster tools
My site map address is ok and Google seems to split the file into 2 (is this normal)?
It sees link from the first part of the split as so :
xmlsitemap.php?fn=vbulletin_sitemap_forum_0_33.xml .gz


However it throws an error for the second part which is :
xmlsitemap.php?fn=vbulletin_sitemap_thread_1_0.xml .gz

The error is :

Sitemap errors and warnings
Line Status Details 2 Missing XML tag
This required tag is missing. Please add it and resubmit. Parent tag: urlset

Tag: url
Problem detected on: May 15, 2010
Could someone shed any light on this please ?

Thanks in advance. __DEFINE_LIKE_SHARE__