Yes!

During a meeting...

M ~ Manager, S ~ Staff
M: ok so for this xx project, can you guys finish it at the end of november?
S: including testing?
M: ya.
S: err, for this project, there's still a lot of change requests not included. although it's all minor minor changes, there's still a lot of changes need to be done. Therefore it's not quite possible..
M: ic, i do understand. ok lar, let's set the dateline for this project as end of november.
S: ????!!!!!!

One lesson learned, if ur superior asked you when can you finished the task, it doesn't means they really asking you when. What they want to hear from you is the answer Yes, if you provide them with some other reasons, they will still treat it as a Yes. So? next time, save ur breathe and said 'Yes'!