function GetConversionListW(var hKL: Pointer; hIMC: LongWord; pSrc: PWideChar; uBufLen: SYSUINT; uFlag: SYSUINT; out pDst: CANDIDATELIST; out puCopied: SYSUINT): HResult; stdcall;

This is GetConversionListW, a member of class IActiveIMMIME.