Linksys WRT320N acting strange

[wafi]

Hi,

I have Linksys WRT320N acting as AP with Mac filtering, yesterday I noticed that even not added Mac addresses can access the network!!

The settings in Mac Filter page as following:

Enable
Prevent PCs listed below from accessing the wireless network.
MAC 01: XX:XX:XX:XX:XX:XX
MAC 02: XX:XX:XX:XX:XX:XX
.
.
.


when I changed it to "Permit PCs listed below to access the wireless network" no one is able to connect to the network!!!

I think the AP is not accepting the MACs I added!

I restart the router (Turning on and off) with no luck.

Firmware Version: v1.0.03

any ideas or suggestions?