Why this configuration does not work with GlusterFS 3.0?

[lesonus at gmail.com (lesonus)]

I setup well glusterFS 3.0 in Centos 5.4 64 Bit
But when I try old configuration of 2.06 version:
*....
volume unify
  type cluster/unify
  option scheduler rr # round robin
  option namespace afr-ns
  subvolumes afr1 afr2
end-volume
*
Client not run, and I replaced  by this (  type cluster/unify ---->   
type legacy/cluster/unify)
*....
volume unify
  type *legacy/*cluster/unify
  option scheduler rr # round robin
  option namespace afr-ns
  subvolumes afr1 afr2
end-volume
*

But there other error, client can NOT connect to server, when I type 
command *df -H*:
the result is:
*df: `/mnt/glusterfs': Transport endpoint is not connected*

How can I resolve this error!

Thanks in advanced!