[Haskell-beginners] Unicode in GHCi

Hello, I'd like to type in GHCi some non-latin characters, but when I try it, no characters are inserted at all. Latin characters though are typed in fine, and in any other shell except GHCi I try non-Latin characters get typed without problem. I mean I'm not able to type in GHCi an expression like 'ᾶ' == 'ᾶ' (can't type in the ᾶ) Is this a known GHCi restriction on the character set it accepts, or something is wrong with my setup of GHCi/terminal? I'm using GHC 6.10.1 in Mac OS X Terminal. Thank you very much, Christos