Health Check interval in OEM 9i Dataguard

I've been going round and round with Oracle support and getting no where. Hopefully one of you can help.  

I'm running 9i OEM and using Dataguard. When you open up the Dataguard application gui, there are 4 tabs: General Data Protection, Properties, and Performance. On the Properties tab, there is one item called Health Check Interval. This field allows me to set an interval of time in hours, mins, or secs. I have it at 10mins.  

My understanding is that this setting causes the broker to check the status of its sites at the given interval. But, I can find nothing in the DRC logs, or on the main Dataguard Broker screen that gets updated. If I do a manual refresh of the status, the field "Last Refreshed on:" gets updated on the screen.  

Oracle is now telling me that this interval is not modifiable and defaults to a minute. I have trouble with that statement since there is a field that I can modify.  

Anyone got any information on how this interval works, where it's updated to (file or screen), etc?  

Thanks

Bob  

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