I just tested unicode font hacks on my K2I from MobileRead wiki, it works like charm.
The process is simple and straigtforward, step 1 is installing the jailbreak, step 2 is installing the font hack. Step 1 will raise a failure as its supposed to, just skip the failure; step 2 does need a manual reboot after the installation to trigger it on.
Detailed instructions could be found on MobileRead.com Wiki.