In order to make this work with z/OS, you need a virtual router (a Linux guest would be the best choice) with two interfaces, one on the VSWITCH, and one on the GLAN with the z/OS guests. Z/OS has special code to allow IPv6 on layer 3 VSWITCHes and GLANs (why IBM thought that having to code special support for every possible protocol was a good idea escapes me entirely...). As noted in the docs, the other option is to share an OSA between the two, which just pushes the complexity into the IOCP.
You could technically do this with MPROUTE and the VM stack, but the syntax is so evil that you really don't want to go there. While you're at it, opening a requirement against z/OS for layer 2 networking support might be a good idea as well. -- db
