In dealing with a FireWall Router mf-firewall  setup and testing, I ran into an issue where my interfaces on my linux box looked like this:
Bonded Interface -> 2 network real network cards
creating device bond0:
The vlan interfaces where all based on the bond0 device, so all traffic went into the vlan device, than off course exited the bond0 device.
Doing a tcpdump on vlan5 for a workstation located there, I could not see the neighbour requests. Doing the same dump on bond0 I could see it.
Of course the device on vlan5 was not getting the neighbour solicit command.
Finally after some research I was able to fix this with this command:
" echo 1 > /proc/sys/net/ipv6/conf/all/proxy_ndp "
Hopefully this can save someone else some grief.
Perhaps someone else has a better fix.