L2_BRIDGE family extension message

MX480 with 15.1F7

I'm migrating irb interfaces from one OSPF routing-instance to another. This only changes the interface unit from ae5.3 to ae5.128. I keep getting this error for every irb (one for each RE)

fpc0 ifl 429 does not have L2_BRIDGE family extension

fpc1 ifl 429 does not have L2_BRIDGE family extension

ae5 {

vlan-tagging;
encapsulation flexible-ethernet-services;
aggregated-ether-options {
minimum-links 1;
link-speed 10g;
lacp {
active;
periodic fast;
}
}

unit 3 {
vlan-id 3;
family inet { 

    address 192.168.90.3/30

I can't find any reference to this error anywhere. Doesn't appear to affect traffic that I can tell.

Some enlightenment would be appreciated.

thanks

Brian Nelson