Cool....I sent activating SMS, then I sent deactivating SMS. Now my phone connects every 15 minutes to network (repeat interval in settings). I uninstalled program, rebooted, but still every 15 minutes my phones connects to network.
Can anybody help? I don't want to reflash it now...

Edit: ha-ha)) I'm stupid. This program just changed connection settings of N900 to "Auto-connect" and "Prefer WLAN if available". I think it should be fixed..