RDS onReadyStateChange

Hi gurus.
Has anybody successfully employed the onReadyStateChange event of the RDS data control?
I've tried all the usual event-handler associations:
onReadyStateChange="myFunction();" as a HTML element attribute,
RDS.onReadyStateChange = myFunction; as script and also
<script FOR="RDS" language="javascript" event="onReadyStateChange">
statements...
</script>
I can't get any joy from this even when my function simply contains an alert. Anybody encountered this problem, orhave a working exapmle of onReadyStateChange for RDS data control. The MSDN is suspiciously vague about it and does not supply an example.

cheers gurus.