change 3648 fixed the player UI.
web will need something similar

I just realised, I am not sure that the web interface supports this feature. 
From the description:
 
"When you select a single song and press PLAY on the remote, you can choose to
play just that song or all the songs in that album or directory, starting with
that song."

that would seem to indicate, remote only feature.

This is a remote only feature.  Punting enhancement post 6.1

Is this fixed in 6.2?

I dont think so.  and with the id's being converted lazily to objects, is likely to be very hard to 
implement.

see bug1825

oh, looks like it may be working, from the remote. the strings were changed to
avoid mentioning folders for 6.1.  If this is working properly for folders,
those strings can be changed back. The strings were changed at svn change 3745