iPhone and Touch both dropping wifi from Airport Extreme

[tocoolu3]

I have had an Airport Extreme for two years now.
I have several devices connected to my wireless network.
MacBook, VistaPC, Printers, AppleTV etc, etc, etc,....
Just recently, my iPhone and the kid's iPod Touch keep getting dropped from the network. The wi-fi icon disappears, and my 3G icon comes up. I'm standing right next to the Airport !!
Sometimes i can reset my wireless and it stays stable for a couple days, but then it happens again.
My MacBook and PC stay connected...no problem.
I'm just having issue with my 'up-to-date' handheld devices..
iPhone 3Gs running 3.1... iPod Touch running 3.0.
Any ideas here?

[ddiMac]

Same here I have a 2009 model of Airport Extreme, and a Semptember 2009 iPod thouch 3g 32gb... it gets dropped pretty often and I can't figure out why? Anyone with hints on what to do?