Hello friends

up to now with my Nokia was all right, but ....

When connecting to WiFi everything is ok, leave the device to run on stand-by after 30 minutes, unlock the device, and the attempt to to open page in Opera or Firefox does not work, ping does not go to google, I have configured mail checking every 5 minutes but first 10-15 minutes is checked, then nothing further checks!
Then disconnect the wifi and the reconnect it and then everything is working properly ping passes, the pages are opened, the mail is checked.

So far everything is working properly on my home wifi I left a cell phone connected to the 7-8h connected to wifi to check email every 30 minutes and is super radlio really do not know why now will no longer ...

I tried to set
- Menu -> Settings -> Internet Connection-> Connection name (edit) -> Advanced-> tab Other-> Power Saving -> and set all 3 options off, on, on max, and the nothing has improved!

I would ask you for help because I do not want more care to reconnect wifi every time you want on the internet!
wifi is: wpa-psk
thank you
ps: sorry for bad english
PPS: I found this link: http://wiki.maemo.org/Wifi_Power_Saving_Mode
But I do not understand how we might be able to help

Maemo version :21.2011.38-1 -and is newly flashed