You can't. It's a limitation of the SQL field type. I hate "sql" fields because they are more often than not database driver dependent and inflexible. In FOF I've enhanced the "list" type field to accept the parameters source_file, source_class, source_method, source_key, source_value and source_translate. As you may have guessed, you can tell FOF to load up a file and use a specific class and (static) method name which returns n options set. Moreover you can opt for additional options not returned by the source method / sql query / model, just by defining them in the XML. You can also control if the options will go through JText or not. In sort, I've created a modern, usable field type. Unfortunately the JForm package doesn't have any of this neat stuff; it's stuck in the state it was years ago, presumably because the people who develop it don't use it in real world software and don't understand its shortcomings.

In so many words, no, you can't have it translated. Bummer.