Apple USB Ethernet Adapter and VLAN??

Bought the Apple USB Ethernet Adapter today because my built in ethernetport on my MBP stopped working. What I know I need to replace the motherboard to have it fixed, so I thought the USB adapter could be useful until then.

But, it didn't work! I only got a "Self assigned ip-address". No matter what I do. I also entered an ip-address manually with no success.

Later at home I tested again, and Voila!! It worked perfectly!

Back at the office, same problem... I only get a "Self assigned ip-address"...

My conclusion of this is that the Apple USB Ethernet Adapter doesn't support VLAN?? Could anyone confirm that or better of, suggest a solution??

Would appreciate it a lot!

PS. Yes we do have Wi-Fi, but it's restricted and is not a solution for me. DS.