When SubText is configured to host multiple Blogs, you'll see http://blogs.hzsolutions.com/vnd/Default.aspx is fine, but http://blogs.hzsolutions.com/vnd/ will return 404 - Not found error code. The simplest solution here is create a real directory and put inside it an empty Default.aspx page, for example i have to create a folder named vnd in order make http://blogs.hzsolutions.com/vnd/ work !
For more detail, take a look at Shiva Manjunath blog at http://theshiva.us/technicalblog/archive/2006/12/14/subtext-error-solution-fix-404-page-not-found-errors-multiple-blogs.aspx