removebug> darcs init
Finished initializing repository.

removebug> mkdir -p src/System/Foo/Bar

removebug> darcs add src/System/Foo/Bar
Adding './src'
Adding './src/System'
Adding './src/System/Foo'
Adding './src/System/Foo/Bar'
Finished adding:
./src
./src/System
./src/System/Foo
./src/System/Foo/Bar

removebug> darcs record -m "add directories"
adddir ./src
Shall I record this change? (1/4)  [ynW...], or ? for more options: a
Finished recording patch 'add directories'

removebug> darcs remove -r src/
Can't remove ./src (it is not empty)
No files were removed.

Ist this the intended behaviour? Of course, 'src' is not empty, that's why 
I passed the '--recursive' option.