11.19.2012

long hostname - kernel tuneable.

Long hostname - longer than 8 characters:

If a server is not properly configured for long host names, the kernel tunable  expanded_node_host_names  needs to be set to1 and the server may need to be rebooted (even though the kernel tunable parameter is dynamic).

I believe this only works if you have certain patches installed or at 11.31 or something, not sure.