CommandLine() function returns a Vector with command line arguments in system enconing. Other parts of U++ uses UTF-8.
Maybe it could be a good idea to convert encoding in SplitCmdLine__() function.
Currently, I'm using a workaround like:
FromSystemCharset(cmd[i])
I guess you are right...
BTW, it is not limited to UTF-8 - that is just the default setting (curiously, not the one we are using in many of our production apps because of historical reasons). You can set it to any encoding you need using SetDefaultCharset.