Migrate from mysql

Hy folks,

I'm trying to migrate a database running on mysql for the famous
www.redmine.org from mysql to postgresql.
I was looking for ressources and I found this :
http://www.olimpiks.ru/2011/03/redmine-mysqlpostgresql-converter.html
The process is almost perfect except for the binary datas.
I have this kind of messages :

/psql:redmine_postgres.sql:155714: ERROR: invalid input syntax for type
bytea
LIGNE 1 : ...TO "wiki_content_versions" VALUES (561,108,108,24,E'h1. Proc...
^
psql:redmine_postgres.sql:155728: ERROR: invalid input syntax for type bytea
LIGNE 1 : ...TO "wiki_content_versions" VALUES (575,113,113,24,E'h1. Open...
/
And other like this :
/psql:redmine_postgres.sql:156648: ERROR: invalid byte sequence for
encoding "UTF8": 0xda 0x75
psql:redmine_postgres.sql:156649: ERROR: invalid byte sequence for
encoding "UTF8": 0xda 0xcb
psql:redmine_postgres.sql:156650: ERROR: invalid byte sequence for
encoding "UTF8": 0xda 0x2d
psql:redmine_postgres.sql:156651: ERROR: invalid byte sequence for
encoding "UTF8": 0xef 0x6e 0xdb
/
Does anyone already manage some migration and have some kind of issue on
bytearray?

Thanks for helping,

regards