I think it's better to do in this way:
1) In project options we have option "Project encoding". It describes
encoding for all *.cpp and *.h (may be *.pro)
2) If we import some source file, we must choose encoding of file.
HaiQ will automatically recode this file to project encoding.
So we have simple way to resolve problem of many encodings.
This is useful for projects with large amount of developers on
different systems. For example, on my work: we have a couple of
computers, there are redhat9 and ASPlinux 11. RedHat9 has KOI8-R as
default codepage, ASPLinux - Windows-1251. So we have troubles... :(
PS. You may look at small tool "recode". You have it in linux by
default, this is a win32-port http://unxutils.sourceforge.net/
recode cp1251..utf8 SomeFile.TXT