Log Message:
Improve GCC version handling:
1.) Set minimum required GCC version to 4.1.3 because that is what has
    been tested. Based on the bug-report it also seems that GCC 4.0.1
    doesn't work.
2.) GCC 4.1.3 (as distributed with NetBSD 5.*) works fine under
    NetBSD/macppc as reported by Matthias Kretschmer on IRCnet.
    So don't insist on GCC 4.2.1 for this platform. This fixes seems
    to fix the build as the GCC 4.4.6 package doesn't build for
    this platform.