FCK Editor related issue

Hi

Presently, in the FCK Editor for the font sizes; xx-small, x-small etc
are given. Can we change it to some other font size e.g., font-size = 11
as the default one? 
What we are doing now is modifying html code (generated inside FCK
Editor) everytime and explicitly give font-size = 11 to make it look
what we want. 

Thanks

Vivek