Cannot add IP address to a bonding interface using WebFIG

RouterOS General
1

On the 20/mar/2013 build of the v6rc12, on a CCR, i cant add IP adresses from the WebGUI to a bonding interface while its possible on both Winbox and the CLI.
The bonding interface is not even shown on the dropdown menu to select the interface for the IP.

[admin@ccr1] > /ip address print where interface=bonding1
Flags: X - disabled, I - invalid, D - dynamic 
 #   ADDRESS            NETWORK         INTERFACE                                                                                                                                                                                 
 2   192.168.40.221/24  192.168.40.0    bonding1

But the address interface is shown as “Unknown” on the WebGUI.