After unsuccessfully messing around trying to disable ipv6 to free those prescious 300kb of memory used by it on my nslu2, I *finally* found out that the rt73 enhanced legacy driver and it's 'make install' command have some nasty sideeffect
It seems [i3njw7ffe]make install[/i3njw7ffe] will always add the line [i3njw7ffe]alias wlan* rt73[/i3njw7ffe] to [i3njw7ffe]/etc/modprobe.conf[/i3njw7ffe] (and will create the file, if it's not there).
Since modprobe does not check the [i3njw7ffe]/etc/modprobe.d/[/i3njw7ffe] directory if it finds a [i3njw7ffe]/etc/modprobe.conf[/i3njw7ffe] file, this completely screwed all alias or blacklist entries I added under /etc/modprobe.d/ trying to disable ipv6. (They were simply never read).
So I think make install should only use modprobe.conf if it already exists and otherwise should add it's entry to /etc/modprobe.d/ralink.
You may have the result of an old build there. The current CVS should put the alias in a file called "ralink" under /etc/modprobe.d when building for 2.6 kernels. You should be able to safely delete anything about ralink that is in modprobe.conf, and delete that file if you have no other use for it.