In SAS9, every dataset should have an "encoding" property that specifies the charset of the bytes in its character variables. You can manually set this without having SAS try to transcode it into a new encoding by using a proc datasets modify.

data work.src(encoding='any');
length s $20;
s = '6E756C6C'x;
output;
s = 'C3B1C3BC6C6C'x;
output;
s = 'C58475C582C582'x;
output;
run;

proc datasets library=work;
modify src / correctencoding=utf8;
run;