Where does ArcGIS temporarily store the WMS tiles?

Hello

I am trying to debug a very weird behavior with ArcGIS for Desktop and WMS feeds (see here for details).

Basically, I can display the WMS feed in ArcCatalog 9.3, but not in ArcMap 9.3.

I would now like to see whether the WMS tiles that are sent back from the server actually reach my computer or whether they are bolcked somewhere by a firewall or something.

I assume that ArcGIS must store the png tiles in any temp folder, but I couldn't find out where it would be. Does anyone have an idea? I would need this information for both 9.3 and 10.1, in case it is different.

Thanks a lot in advance and best wishes from Switzerland

Stéphane