If you put it in a different directory, perhaps one set aside just for fonts, use relative urls.
Examples:
1) Font in same directory, use "font_name.fdb"
2) Font in a directory named fonts in the same directory as the ming script, use "fonts/font_name.fdb"
3) Font in the directory above the directory containing the ming script, use "../font_name.fdb"
4) Font in a directory named fonts located in the same parent directory as the directory containing the ming script, use "../fonts/font_name.fdb" Just your basic relative url.
I don't believe we can use full urls, but I honestly haven't tried yet.
Click Here for the Ming Fonts.
Click Here to see lesson 5.