The URL listed fornet-misc/vmnet does not respond. * net-misc/vmnet [ Masked ] Latest version available: 0.4 Latest version installed: [ Not Installed ] Size of downloaded files: 16 kB Homepage: ftp://ftp.xos.nl/pub/linux/vmnet/ A tcptraceroute on port 21 fails at what I can only guess is one or two hops above what would be the ftp server. A search for vmnet does not reveal anything useful.
Read the comments in the ebuild. The upstream site is often unreachable outside of .nl. The tarball is available on the gentoo mirrors. I updated the description.