Trying to give something back to the Community...
Symptoms
MOM 2005 Reports with an end date of 01/01/2010 or later result in incorrect date values on the X-axis.
http://support.microsoft.com/kb/2012828
Read the complete post at http://wmug.co.uk/blogs/cliffs_blog/archive/2010/01/11/ms-kbs-new-kb-mom-2005-reports-have-incorrect-date-values-on-the-x-axis.aspx