The actual stable, fails to compile against =sys-libs/zlib-1.2.5.1-r2. A new version should fix this issue, so please change the summary with exact version and add arches. Thanks in advance.
I've fixed gdal-1.6.3-r1 with sed to work with new zlib so it doesn't hold up bug 384483. But I'm leaving this bug open since stabilizing new gdal might still be a good idea, just as an enhancement.
Adding arches, lets see.
x86, ppc and amd64 done.
ppc64 done; closing as last arch