Odd sized fonts in WLM

I would like to use Arial 11 for composing emails but no odd numbered font sizes appear in the drop down list in WLM.  I have tried Options>Mail>Compose>Font settings, select 11 and apply OK.  The 11 remains in that location but the actual program always reverts to the nearest even number; in this case 10 which is too small.

I can’t see why a program that contains access to dozens of font designs in its drop down list is nonetheless so very limited in font sizes.  Is there a simple fix that I’m missing?