VLAN renaming issues on startup. Claims resource is busy

[jantypas]

I've got two Gentoo boxes, both running the 2.6.19-r5 kernerl and the same config.
One box has two ethernet cards (tg3, and 3c5xx), one has three (e1000, 3c5xx and 8139too).
On the systme with two cards, I can create vlans either by vconfig or the net file. For example, if I create a VLAN on eth1 witht he command:

vconfig add eth1 100

It will work, and ifconfig will now show eth1.100 and proc/net/vlan will show this vlan.

If I do the same task on the other machine, I can create hte VLAN, and it does show up in proc, but it has the name:

eth1.100_rename

Message logs say the module can't rename eth1 becuase the resource is in use.

What am I missing?