1. Download a legal .ttf font from the internet
2. Make 4 copies of the font file and name them as below:
3. Place them in a folder called Fonts
4. Connect your phone and select Mass Storage USB connection mode
5. Browse to your Memory card (E) > Resource folder and place the the Font folder in there.
6. Reboot your phone to see the new fonts you've just installed.
Make sure that you connect your phone in Mass Storage mode to be able to see the resources folder.