After upgrading from 5.2 to 6.0, the tetex packages aren't installed properly with many missing files. Running latex on almost any file fails due to missing files (such as article.cls).
*** This bug has been marked as a duplicate of 2727 ***The problem is/was in rpm. Manually deinstalling and reinstalling the packages will correct this problem.
*** This bug has been marked as a duplicate of bug 2727 ***