Sorry - this got lost in my list of posts.
It's not what I thought it might be (that your router was a different type of wireless than your iPhone).
Here's a few things that might help -
How to put in a password HEX key:
http://www.macrumors.com/iphone/2007/06/30/unable-to-access-password-wifi-networ ks/
and here's a fix someone's been posting a lot on these boards that seems to help people:
You may have an incorrect password. iPhone does not show password errors, it will look like you are connected via wi-fi(fan icon displays) but once you try to surf the web it will switch over to edge.
This fix has worked for a lot of people.
1.) unplug router for AT LEAST 10 minutes
2.) reset network settings on iPhone [go to SETTINGS, then to GENERAL, then to NETWORK... then hit RESET NETWORK SETTINGS]
3.) power down iPhone [hold sleep/wake button 8 secs, then slide slider to off]
4.) turn on router [wait about 5 minutes for it to fully cycle up]
5.) Go to settings - WiFi - choose your network - when the password screen comes up, switch to Hex/ AscII, then enter password [no $] press enter. (note - may be caps sensitive)
Hope one of those helps!
Aym