My setup is as folows:
router: Dlink DSL 2640B
linkstation (connected wired with the router): LS-XL9FF
rest (connected wireless with the router): iphone 3gs ios 5.x, ipod touch ios 5.x, macbook, imac
Itunes server is up and I can connect to it with my macbook,imac.
I want to stream music via Airplay (i don't want to install and use the webaccess app) to my iphone. But the airplay symbol doesn't appear in the iphone settings.
My best guess is that it will be sufficient if I open up UDP port 554 on the router.