ng_ether and interface naming (bug or feature?)

[Denis Peplin]

Hello!

I have found, that changing interface names from rc.conf
can break ng_ether when it loaded from loader.conf or
compiled into kernel.

For example, when mpd is used as PPPoE server, rc.conf
contain ifconfig_fxp0_name="net1" and /boot/loader.conf
contain ng_ether_load="YES", the mpd logs:

exec: /sbin/ifconfig net1 up
Cannot send a netgraph message: net1::No such file or directory
Error in creation ng_pppoe node on net1:

There only two workarounds: avoid using interface naming, or
loading ng_ether after renaming interfaces.

Is this a bug or a feature, that just wait somebody to document it?