Not at all.
I think the question of "is it right?" or "is it ethical?" is a much more important and compelling question.
Is it to be defined as rape? Well, if the consent was under intoxication it's technically still consent. So you cannot call it "rape". People who call it rape either refuse to take personal responsibility, or don't believe people need to take personal responsibility for how much they drink, or what substances they consume, and the situations they get themselves into.
If someone wakes up and realises they agreed to having sex with someone while intoxicated, can they then turn around and say "that person raped me"? No. You made the decision to drink too much or take too much drugs, and then made another decision to have sex with someone else. Take some fucking responsibility.
Not to say that people can't take advantage of another's intoxication. And it's not to say that people are rightful in taking such advantage. But it is not to be defined as "rape". Not in my opinion at least. It's still consensual, but the intoxicated person consented while, well, intoxicated.
Are you really completely powerless when you are intoxicated? Are the decisions you make when drunk not really your responsibility? If you don't want people to take advantage of you when you're intoxicated...don't drink or take drugs then. Simple. It is a well known fact that if you do so, you are bound to make stupid decisions. Own up to your actions.
This seems to be the inversion of the other thread, about guys saying it's okay to rape someone who is dressed like a slut, because "they were asking for it". It's people making stupid decisions and blaming it on someone else, refusing to take personal responsibility for decisions they made and asserting themselves as powerless and helpless victims.
And I'm definitely not saying raping someone who is drunk is okay. I'm saying that if someone consents to sex, regardless of their sobriety, then it's a "yes", and it can no longer be defined as rape.
EDIT: I understand the law does define this as "rape". However I for one completely reject this notion, and I believe this law should be revised. And I definitely reject the notion that the law is always right. I believe that the law is seldom right.