Are the below statements equivalent?

[Machine Code via Digitalmars-d-learn]

Give:

enum Foo { a, b, c, d, e }
Foo f = Foo.c;
Are the below statements equivalent?

switch(f) {
    case Foo.a:
    case Foo.b:
         doSomething();
    break;
   // ...
}

and:

(note the comma in the case)

switch(f) {
   case Foo.a, Foo.b: doSomething(); break;
   // ...
}

I found it in some source code, tested and it does work but is 
this the standard behavior?