ESS iviews "SAP graphics data not supported" message

The message "SAP graphics data not supported" is displayed when some ESS services/iviews are displyed (eg PZ03, PZ09, PZ17), either when run through the portal (EP6 SP2) or directly on the ITS (6.20).

The portal logs the message below:

"com.sap.portal.appintegrator.sap.IAC_Configuration' not found - IGNORED. Reason: com.sapportals.portal.prt.service.ServiceException: Service not found: com.sap.portal.appintegrator.sap.IAC_Configuration"

In some cases it is displayed as a windows popup (eg when it occurs on PZ09) and others in the infoline/status bar area (eg on PZ03).

Does anyone have any ideas on how to prevent/correct this message?

Thanks

Ross