Following are the kernel .configs needed for containers:

CONFIG_VETH=y
CONFIG_MACVLAN=y
CONFIG_SECURITY_FILE_CAPABILITIES=y
CONFIG_CGROUP_DEVICE=y
CONFIG_UTS_NS=y
CONFIG_IPC_NS=y
CONFIG_USER_NS=y
CONFIG_PID_NS=y
CONFIG_NET_NS=y
CONFIG_DEVPTS_MULTIPLE_INSTANCES=y
CONFIG_CGROUP_FREEZER=y
CONFIG_CGROUP_NS=y
CONFIG_CGROUP_SCHED=y
CONFIG_CGROUP_CPUACCT=y
CONFIG_CGROUP_MEM_RES_CTLR=y

All features are upstream as of  2.6.29.

See previous comment for needed .config variables.

Assigning this to Peter Bogdanovic at IBM.

All features are upstream as of  2.6.29.

See comment #1 for needed .config variables.

------- Comment From sergeh.com 2010-05-04 15:30 EDT-------
The network namespaces do not appear to be working.  The following recipe succeeds on a mainline
kernel, but fails on 2.6.32-19.el6.ppc64

Open two terminals as root.

Terminal 1:
git clone git://git.sr71.net/~hallyn/cr_tests.git
cd cr_tests
git checkout ns_exec
make ns_exec
./ns_exec -cmnp /bin/bash # this starts a new shell
mount -t proc proc /proc

Terminal 2:
# the next two lines try to set 'pid' to the pid of the shell which is child of ns_exec
p2=`pidof -s ns_exec`
pid=`pstree $p2 -p | awk -F\( '{ print $3 '} | awk -F\) '{ print $1 '}`
ip link add type veth
ip link set veth1 netns $pid   # here you use the pid found above
ifconfig veth0 192.168.1.1 up
nc -l 192.168.1.1 9999

Terminal 1:
ifconfig veth1 192.168.1.2 up
route add -host 192.168.1.1 dev veth1
echo hi | nc 192.168.1.1 9999

Expected result:  'hi' shows up in Terminal 2.  This happens with mainstream kernel,
but not on 2.6.32-19.el6.ppc64

------- Comment From sergeh.com 2010-05-04 15:50 EDT-------
Sorry, Dan Smith points out i was defeated by the firewall.

All containers functionality appears to be present and functioning.