--- Operating System, Graphics card ---
Ubuntu 64, 16gb ram, 2* nvidia gtx560tioc

--- Blender version with error, and version that worked ---
current trunk does not work (just compiled myself a clean one and tried a buildbot build)

--- Short description of error ---
I'd like to show the vertex weights while in edit mode and have a modifier on my plane that alters the vertex weight. When I set up the modifier to show up in edit mode too, the mesh hides all its weights and looks like as I've never ticked the "show weights" checkbox.

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---
Open the blend, go into the edit mode (if not already in it) and click on the modifiers "Use modifier while in edit mode" -> The weights will disappear.

Greetings, Thomas