Changes to default font ignored

[David Rosenstrauch]

Not sure what the problem is, but when I try to change the default font 
in Xfce it doesn't seem to take effect.  In "Settings -> Appearance -> 
Fonts -> Default Font" I've been setting the font smaller.  But it 
doesn't seem to have any effect.  When I open Thunar again (as well as 
other Xfce apps) fonts are the same size as before.

Something I'm missing here?

Thanks,

DR