wake and sleep viper board with PXA255

Hi

I have a viper board with a PXA255 (kernel Linux viper 2.6.21.7-ael2
#1 Fri May 2 14:30:18 BST 2008 armv5tel unknown) and I would like the
board to wake up when data is coming on the port COM4 (external
interrupt GPIO4).
I have a PC connected to it with a serial connection and minicom. I
can talk to the viper board. I use the viper-sleep.sh script provided
and I have just added the pin 4 (GPIO4) to wake up the board from
sleep. It doesn't work when I type characters on the PC.

Thanks for any advice

Karim

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