Create booleans in Bryce 7 and import them into Poser: the normals are messed up.

I wanted to create a wall with a hole and more complex objects.
I collapsed the boolean object in Brye and exported it as an obj-file.
Imported it into Poser (7).
Although the rendered images look not too bad IMHO, it's quite annoying.

I treid the option Make Polygon Normals consistent, but it doesn't work so far.
The Poser group editor is a bit tedious.

Is it a bug ??
Is there a way or a tool to fix this issue ??

Thanks in advance.

See screenshots.