After UTF8 migration, i can see junk characters in my reports6i ouptut (TEXT or PDF)

 After  UTF8 migration, i can see junk characters in my reports6i ouptut (TEST or PDF) :

French accents or greek characters (multibytes characters)

Could you please help me to solve this issue?

Is it a reports 6i issue? (reports can't handle mutli bytes characters in TEXT or PDF mode)

Is it a reports setup issue?

DO i need to migrate all reports (custom and standard) to xml publisher and use XML publisher?

Thanks fo ryour help