ok i have attached 2 ttf files.
one is ORIGINAL SE ttf file and the other is random one i selected.
install both to WINDOWS/FONTS folder and then open them with CHARACTER MAP viewer.
note the difference between 2 files and lack of characters in random ttf file compared to original SE ttf.
this difference is the directly affecting the view of characters and language specific letters in the phone.
note as well the difference in file size.
so conclusion is that the bigger ttf file size you have, the most likely it is possible that ttf file will be displayed properly in SE phone with most, if not all, characters and language specific letters.