I grabbed some google code .. and created a function that can handle the various exceptions. The UDM is a simple call to this function.
CREATE OR REPLACE FUNCTION dblink_check
THEN return 0;
THEN RETURN 0;
Close .. atleast in 10.2 there is Metric Error . .but only for Database UDMs. For some reason that functionality isnt there for host based UDM.
Create Notifcation Rule
Select Target Type: Host
Select Availability tab, shows Agent reachable/unreachable and blackout
If you choose
Target Type: Database
Select Availability tab, shows Agent reachable/unreachable and blackout PLUS Metric Error detected/Resolved
This seems like it would have been the perfect answer.