While trying to install the latest version of PPC64 OpenSuse Tumbleweed on my powermac g5, I keep getting the error "http://download.opensuse.org/ports/ppc/tumbleweed/repo/oss/repodata/repomd.xml: Invalid Signature. Installation aborted." Same thing happens when using the dvd version of the installer as well, and I cannot progress from this point. Any suggestions? Thanks.