I am using the scale bar of the QGIS composer (ver 1.8) and I don't understand how the whole thing works.
Where can I set the units properly? The layers have idential CRS (WGS84), the settings for map tools is in meters.
I have tried to get it correctly by changing segment size and map units per bar unit, but it doesn't work. However, I have to admit that I don't understand what these two fields actually mean.