WDS on Linksys WRT54G & Aiport Express Drops

Hi,

I have recently set up a WDS link between my WRT54G and Airport Express. I
have implemented MAC address filtering and have set up WEP 40 bit.

The set up works fine with all three of my computers. I am able to play
music and all is well. However every half day or so the WDS link between the
WRT54G and Airport Express fails with the Airport showing the yellow
flashing light. I have established that if I turn off the airport the
problem persists. If however I turn off the WRT54G and turn it back on then
the link fires up again and everythink works for half a day or so.

Can anyone offer any advise.

Thanks,

Carl.