[otrs] utf8 & otrs database

Hello, I run otrs with a database hosted on a mysql5 server which is not on utf8 by default. However, otrs' database is encoded in utf8. During the upgrade, this caused troubles (strange characters appeared). I think this is due to the fact that the db upgrade script do not specify a charset and rely on the global default in mysql's my.cnf file. Would anyone have an idea how to solve that without turning the whole mysql into utf8 ? Thanks in advance, -- Mikael Kermorgant