Don't know if it works for browser anyway... conenct the KT to PC, create a fonts (no caps) directory in the root. Put there your TTF files (I suggest you this UniFont that supports whole UniCode:
http://unifoundry.com/unifont-5.1.20080907.zip) and then you are able to use your own fonts, even Japanese (
http://atouchofkobo.wordpress.com/2011/08/28/260/) with the EPUBs. I thinki it could work for browser also...