Comment 3 for bug 1539720

dosfstools on precise does not provide mkfs.fat, only mkfs.vfat.
precise:
$ ls -l /sbin/mkfs.*fat
lrwxrwxrwx 1 root root 7 May 1 2015 /sbin/mkfs.vfat -> mkdosfs

$ dpkg-query --show dosfstools
dosfstools 3.0.12-1ubuntu1.2

trusty
$ ls -l /sbin/mkfs.*fat
-rwxr-xr-x 1 root root 27608 Mar 18 2014 /sbin/mkfs.fat
lrwxrwxrwx 1 root root 8 Mar 18 2014 /sbin/mkfs.vfat -> mkfs.fat
$ dpkg-query --show dosfstools
dosfstools 3.0.26-1