CoS-clue quote

[Berit Jakobsen]

No: HPFGUIDX 90415

Mandy wrote:
There is excitement on MuggleNet about the discovery of a new clue 
concerning the Chamber of Secrets. And JKR herself said she almost 
gave it all away in book 2.

Berit replies:

Please; could anyone tell me where to find the interview where 
Rowling said this about the clues of book 2? I can't find it.

Berit
http://home.no.net/berjakob/snape.html