Support non-Latin characters

Feature requested
Support for non-Latin alphabets in invoices.

Typical use case
For use by businesses that work with clients outside of the UK and use non-European languages (such as Japanese and Chinese)

How I would expect it to work
Allow for the display of non-Latin characters in invoices etc. At the moment, when I input Japanese, it initially shows correctly, then changes to a series of question marks when I save the invoice. This is fine for some of my clients that can read both English and Japanese, but I will need Japanese display for my clients who only read Japanese.