Problem with japanese games.
 

Does anybody know why some (not all!) japanese games won't work with my PAL-Console ?
Neither Utopia 1.x nor Codebreaker are able to boot them. On the other hand there are a couple of jap titles running without any problems. Where is the difference between them?

Try PAL Patcher (either "50 Hz to 60 Hz", or "PAL Protection 1", or "PAL Protection 2").

Isn't the PAL patcher a tool used for modifying backups or does it boot the recommended bios or whatever needed to play imported games?
I'm using the original GD ROMs...

So it won't help you : it's supposed to patch protection in some games. Your imported games are bound to be protected.
Maybe you could try a boot CD called "DC-X game adaptor".

Ok i'll try that one.
But isn't it strange that several titles are running great with both utopia and codebreaker discs and others won't?
Is there another protection but this region-code like thing making imports unplayable? Most of the FAQs are giving detailed information about how to fix backups but they don't mention this problem occuring with originals.