Mara,
thank you for your reply. Unfortunately, power saving is supported by my router (isn't MIMO power-save mode is a required feature in the draft-n?[1]). I link the complete technical specifications. I'm also using this function with other devices (like my N82). I think there is an incompatibility or a bug with n800 software implementation . Looks like I'm not the only one.

I bough my N800 around may 2007 at the NY nokia flagship shop and I suppose it is a first revision hardware. I please you to take a look at the bug page at maemo.org.

best regards,
Mattia

[1] http://www.macsimumnews.com/index.ph...irport_extreme