Firmware 1.0.1.18 & WOL

I recently installed Firmware 1.0.1.18 on my WNDR4500 and am having an unusual problem that occurred immediately. I use WOL through a Magic Packet to turn my network on every weekday morning. The computers are on all day long and then shut down at night after performing a backup. Since installing the new firmware, they are all receiving WOL signals all day long, even if the network computer that issues the Magic Packet to the local network is turned off. The only way to prevent the computers from firing up every few minutes is to disconnect the LAN cable or the power cable from the various computers. I have no need to use WOL across the WAN and only wish to use it on the LAN. Does anyone have any idea what is happening here and what settings I need to make to keep WOL locally, but prevent it from coming in from somewhere outside the network or from the router, whichever might be causing this?

Thanks.