Sorry, no. The subject is always in the subjective case: he, she, it, we, you, they, who, whoever. It is the object which takes the objective case: him, her, it, us, you, them, whom, whomever. So “whoever it is” is correct.

Actually, in this instance it doesn’t matter whether “whoever” or “it” is the subject of the clause, because the verb to be doesn’t take an object, it takes a complement, which is always in the subjective case anyway. Hence “it is he” is correct, “it is him” is not.

Well, that’s what was (still is?) taught in traditional English grammar, which is modelled on the classical languages Latin and ancient Greek. In those languages distinctions of case are vitally important. It is debatable whether the classical rules apply to English. Hence, many English speakers say (and write) “it is him,” although pedants (like me) prefer “it is he”. Consider the following from the Gospel of John (18:4–5a) in a modern English translation (NIV):

Jesus, knowing all that was going to happen to him, went out and asked them, “Who is it you want?”
“Jesus of Nazareth,” they replied.
“I am he,” Jesus said.

(Note also the use of “who” in “Who is it you want?” If Jesus had used the verb to seek instead of the verb to be, it would have been “Whom do you seek?”)

But anyway, “whomever it is” just sounds wrong!

Thank you for the explanation. Oddly enough, i said to myself "it is she" and even posted it (then quickly removed it.) I had it in my head that although "she" was the correct word, it was the same as "her." Heh. I'm still learning the rules (but actually caring more of late) so i'm glad you corrected it. This is one of the best ways to lean the rules. That is, saying what you think, and being corrected when wrong.

the unknown person is the subject of the clause

Exactly. And that means "who", not "whom".

You know, it's fine to be wrong. But it's not so fine to go "correcting" someone else with your wrongness.

You've handled your corrections with grace, though, so I kudologize you for that. :-)

it's not so fine to go "correcting" someone else with your wrongness.

Considering i thought i was correct and i wrote, "i believe that should be," which denotes not being sure, i would not consider that "correcting." Rather, "suggesting."

Your lack of certainty should be a weight to the importance of making a public declaration of the incorrectness (that your perceive). As should the significance of the perceived errors, of course.

Pedants are often perceived as nuisances. They tend to have exaggerated certainty. This contributes to a pedant over-estimating the importance of a correction which can lead one to publicly declare such despite it's insignificance to the actual content of the discussion. See also: nitpicking.

Asking "Shouldn't it be 'whomever'?" in the Chatterbox seems a more appropriate approach for this particular distraction. Though, it appears that fewer would have been amused by you in that case.

"whom" is always preceded by "to", "with", "at" or similar

"whom" is always preceded by "to", "with", "at" or similar.

Only when it's the object of a preposition. Not when it's a different use of the objective case, such as the direct objects in, "Whom do you love?" and, "The man whom I had hired called in sick."

Aaron B.
Available for small or large Perl jobs and *nix system administration; see my home node.

Really? I was taught "who" is used for direct objects, and "whom" is used for indirect objects. But a search shows you're right; that's wrong.