restrict access via Master mode

[li1_getoo]

i got a prism54

like te subject says i am trying to restrict access via Master mode by

iwconfig eth0 mode Master
iwconfig eth0 essid foo
iwpriv eth0 setPolicy 2
iwpriv eth0 addMac xx:xx:xx:xx:xx..
ifconfig eth0 up

and this is wehre the problem is dhcpcd eth0 and it just hangs

if anyone got this to work please tell me whats the proper way on get it done , thank u very much