How about this:

procedure TIBODataset.SetBookmarkData( Buffer: TRecordBuffer; Data:
Pointer );
var
RecInfo: PIBORecInfo;
AHexText: AnsiString;
begin
RecInfo := PIBORecInfo(Buffer + FRecInfoOfs);
if Assigned( RecInfo.RecRowNode ) then
begin
AHexText := StrPas( PAnsiChar( TRecordBuffer( Data )));
HexTextToBinary( AHexText,
RecInfo.RecRowNode.KeyData,
BookmarkSize div 2 );
end;
end;


Thanks,
Jason Wharton