Absolute temp value in tray icon

I get no minus sign in the tray icon when the temperature goes under 0 degrees celsius (which is about all the time here i northern Sweden at this time a year). Is that a known problem?

At the moment the temperature says -3 in the current conditions window, but in the tray icon it just says 3 degrees. I?ve tried different fonts and sizes, but that doesn?t help.

Skier, windsurfer, archer.