order() and sort() on single row data.frames

Hi,

not sure whether this belongs here or has been reported/asked before.

In the current R devel the behavior of order() and sort() on data.frames 
with a single row has changed.

Before (release):

 > sort(data.frame("b", "a"))
 ? X.a. X.b.
1??? a??? b

Now (devel):

 > sort(data.frame("b", "a"))
 ? X.b.
1??? b

I did not find any specific documentation in the daily news log on this.

Thanks,
Benjamin