Viewing "Current Acitivity"

When I tried to view the "Current Acitivity" using Enterprise Manager, , I
got " 0 idle connections and 0 active connections". The window is basically
empty.  I tried running one application that connects to that server and I
still get nothing. I know that even there is no active connections, I
shoulkd get something for "sa" and "system". But when I run sp_who, I got
some list of active and idle connections.

I shutdown and restarted the Server hoping it was just a glitch.
Unfortuntely, It didn't help.

Please help! Thanks.