Interpretation of 注意する: to warn or to be warned?

Question

I'm uncertain about the usage of 注意する in this sentence from Japanese the Manga Way, Chapter 25 page 198. The context is that a woman has noticed the following message written on the back of her husband the section chief, presumably by his subordinates. The translation is that given by the textbook.

課長は酔うと裸になるので、奥さまから注意してください。
When your husband gets drunk, he takes off his clothes, so please caution him.

The textbook goes on to define 注意する as "to warn/caution", and explains that から marks　奥さま as the source of the action. But isn't she the subject of 注意する, the one doing the warning? If it was the passive 注意させる I could understand, but it isn't. To me this sounds more grammatical:

課長は酔うと裸になるので、(奥さまが)注意してください。

Alternatively, I'm aware that 注意する can also mean "to pay attention/to be careful", so maybe the 奥さまから注意してください is actually a request to the section chief, i.e. please be alerted to your behaviour (from your wife). Then 課長 is the subject of 注意する, which now means "to be warned/aware". This seems rather like a passive construction in disguise.

What is the correct interpretation of 注意する in this context?

Answer 1

It is unambiguous that the wife is the one who would be doing the warning, and this sentence is being spoken to her, by the boss, who is directly asking her to caution her husband.

The function of から is really very similar to "from" in English, as in going from point A to point B, last from time A to time B, being made from something, and others, but especially in this case, hearing something from someone. Therefore the usage of から in this case basically mirrors the English meaning: the boss wants the husband to hear it from the wife. It might be slightly confusing because we don't use "from" as a command like that in English. Like you can't say "Please caution your husband from yourself."

The grammar of から in this case might be debatable, though. The following is my original interpretation, with amendments later:

I admit I am kind of speculating here, but my assumption is that から is not playing the exact role of が. When you make commands there is an implied subject, so even though you don't include the subject marker in （～が）～してください, it is understood. The 奥様から in this case is emphasizing that he wants the wife to caution the husband herself, but since there's no が and he's explicitly saying 奥さまから, it kind of sounds like から is replacing が.

Another way to say it might be （奥さまが）自分から注意してください。 I don't know about you, but to me it feels a little more obvious that way, and the separation of the subject version of 奥さま and the origin-of-action version of 奥さま is shown.

EDIT:

The discussion in the comments has led to the suggestion that から may in fact be able to mark the subject. If this is true then 奥さまが自分から注意してください is technically different. If we permit から to be a subject marker then the sentence can be interpreted as is: 奥さま（から・が）注意してください。

Answer 2

I don't think that 注意する can mean "to be warned" because "to be warned" is a passive construction that would correspond to the 注意される inflection. 注意　means both caution and warning, so 注意する can mean heeding a warning and giving a warning.

Jim Breen's WWWJDIC provides not only a dictionary entry for 注意, but 371 example sentences containing 注意.

またこれをしたら罰せられることを私は君に注意しなければならない。
I must warn you that if you do this again you will be punished. 

君たちは彼の話に注意を払うべきだ。
You should pay attention to his story.