Quick Question:

(1) This is she, who is speaking.
(2) This is her, to whom you are speaking.

Are both of those sentences grammatically correct, or only the first one? If the 2nd is not grammatically incorrect, then I could see answering the phone with an abbreviated version of that implied longer sentence, shortening it to "This is her...".

If the 2nd sentence is grammatically incorrect, would the correct formulation then be: "This is she, to whom you are speaking?"