I have tried both ad-hoc networks and routers, no encryption and WPA2. I see networks in range but cannot successfully connect to any networks. Network manager tries to connect then says that the netowork has disconnected. I can connect perfectly fine on my laptop and Nokia N900. I am sure my router does not have a MAC filter.
follow this how to for your n900
http://forums.internettablettalk.com/showthread.php?t=58570, but use the script below. you can then connect your n900 to your ad-hoc wifi at home, pair it by bluetooth to the pandora, run this script and you will be able to connect to your n900 as a bluetooth access point. not using your data plan but your home wifi through the n900.
#!/bin/sh
# by 9000 @ talk.maemo.org
# Prompt you to select the Internet connection. You may choose gprs or wifi
run-standalone.sh dbus-send --system --type=method_call --dest=com.nokia.icd_ui /com/nokia/icd_ui com.nokia.icd_u
# Selecting and establishing connection takes time
sleep 10
# Verbose mode. You can remove it when you're using widget to activate this script
set -x
IP_ADDR="192.168.3.1"
NETMASK="255.255.255.0"
DHCP_RANGE="192.168.3.100,192.168.3.127"
RUNFILE="/var/run/btpan_tethering.pid"
DNSMASQ="/usr/sbin/dnsmasq"
# Load modules
modprobe ipt_MASQUERADE
# flush old rules
iptables -F
iptables -t nat -F
iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE
# forward IPs
echo 1 > /proc/sys/net/ipv4/ip_forward
# Setup bnep0
ifconfig bnep0 down
ifconfig bnep0 up
ifconfig bnep0 $IP_ADDR netmask $NETMASK up
# Setup DNS and DHCP
start-stop-daemon -S -p $RUNFILE -m -b -x $DNSMASQ -- -k -I lo -z -a $IP_ADDR -F $DHCP_RANGE -b
run-standalone.sh dbus-send --type=method_call --dest=org.freedesktop.Notifications /org/freedesktop/Notifications org.freedesktop.Notifications.SystemNoteInfoprint string:'Bluetooth WIFI Activated'