[Pharo-project] Does FFI support WideStrings?

Hi. Someone pointed out here: http://stackoverflow.com/questions/5212790/unicode-characters-in-a-smalltalk... a problem while using WideStrings with FFI. FFI throws a "Could not coerce arguments". Is this because of the usage of WideString? what we should use instead (I know that ByteString works) ? can we fix FFI so that it supports WideStrings? thanks Mariano