uim_code_converter is used to abstract platform-dependent code convereter. But current libuim is assuming that converted string is an ordinary C storage and simply free() sometime. This is inappropriate for object oriented string such as QString in Qt. See IMKit-uim 0.4.2 for actual code.
The encoding conversion responsibility should be moved to bridges in future version of uim. And for the case in IMKit-uim, the encoding conversion should be performed in IMKit layer, by cancel the automatic encodidng conversion of libuim by specifying client encoding as same as IM's.
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