Short post.
This is tested in the Bakpia mod kernel (2.6.32.9), module compiled from the rmcc github kernel 2.6.32.9 branch located here.
Compiled in a CentOS 5.3 environment with android ndk and sdk installed.
Anyways, copy the module to /system/lib/modules do an insmod tun.ko to run the module and tunneling is all set. You can now use Openvpn downloaded from the Market.
nice nice nice nice! openVPN for those low battery consuming ROMs! thank you very much!