Different screen-resolutions makes desktop icons disappear

[olef]

Running Windows 7 pro
Dexpot ver 1.5.14 build 1777
4 Virtual Desktops

3 desktops configured to 1680*1050
1 desktop (desktop 4) configured to 1024*768

Desktop Icons are only placed on Dektop 1, no icons
When switching between desktop 1,2 and 3 everything seems to work fine (same scree-resolution)
When switching to desktop 4 (1024*768) everything still seems fine, but when swithing back to desktop 1 all icons has disappeared.
When looking in "Desktop Windows", all the Icons have moved to the "Hidden"-Group.