How to change feature weights for standard graphics layer programmatically??

Hey all,

I wrote some ArcObjects code (ArcGIS 9.2, VB.NET) which creates some graphic elements programmatically and then exports the map. some labels that overlap with the graphic features are not displayed. the "manual" solution is to open the Labeling toolbar, click on "Label Weight Ranking" and set the feature weight of the standard layer to "none". I would like to change the feature weights programmatically.
Does anybody know which interfaces I can use in order to access the feature weights of the standard layer??

Thank you in advance for you help!

Regards,
Johannes