Reliability Monitor Stuck On 01/01/1970

Having recently upgraded to Vista Home Premium I have come across the
Reliability Monitor but unfortunatley the only dates that show up on it are
01/01/1970. when I click on another date there is none. The performance
monitor seems to be working fine along with the problem solving and solutions
feature which shows the correct dates of problems that have arisen. It is
just the reliability monitor which does not seem to be showing any relevant
data. I have searched this newsgroup and found a post how to enable the rac
agent which was already enabled so I am at a complete loss. Any help would be
greatly appreciated.
Many thanks David