multi pppoe with VLAN

now i have some problem
i can’t connet muti ppoe-client with vlan

ether1 - lannetwork
ether2 - Vlan id 11 ,12 ,13 ,14
ppoe-client1 Vlan id 11
ppoe-client2 Vlan id 12
ppoe-client3 Vlan id 13
ppoe-client4 Vlan id 14

i can connet only one ppoe-client1
the ppoe-client2 ,3 ,4, can’t connet

my system
routeros3.18
lancard duo gigabit intel server
swith L2 3com

** when i try change to ubuntu server it ok
**multi ppoe 1,2,3,4 All connet ok
** help meeeeeee thankkkssssssss

see /log print

maybe it’s because all vlans have the same MAC address? then http://wiki.mikrotik.com/wiki/Change_MAC_address_of_VLAN_interface