Cross-subnet AirTunes -- doesn't work?

Question

I'm having a problem playing tunes to my AirPort Express, though mind you my setup is strange.
The AX works fine if I'm on the same IP subnet that it is on, but if I access it from another subnet, iTunes tries to connect for about a minute then silently gives up. I forward mDNS (Bonjour) from one subnet to the other using Avahi (which works for plenty of other things), and there is no firewall between subnets, just plain routing. I've tried with iTunes on 10.4, 10.5, and Windows and all do the same.
Is this doomed to fail? Why?

Answer 1

You need to configure the Airport Express to join your existing wireless network in client mode.
This will allow you to continue to use your existing wireless network and stream iTunes to your Airport base station.
One of the problems with WEP is that the actual standard relies on a 10 character HEX key for 40bit WEP and a 26 character HEX key for 128bit WEP.
In order to make things easier for people, vendors use certain algorithms to convert simple alphanumeric passwords (or passphrases) into HEX keys, thus enabling people to use simple memorable WEP password rather than lengthy HEX keys.
The problem is that different vendors use different algorithms to generate the HEX key and therefore a ASCII password on an AEBS will be hashed differently on a Netgear client and vice versa.
One thing is a 13 character 128 bit WEP password will be hashed by all vendors in the same way (if you use 40bit WEP then a 5 character password is required).
Though sometimes not even that works and the HEX key must be used regardless.
AirPort: Joining an encrypted wireless network
http://docs.info.apple.com/article.html?artnum=106424
Choosing a password for networks that use Wired Equivalent Privacy (WEP)
http://docs.info.apple.com/article.html?artnum=108058
iFelix