I'm having a similar problem here. I had summitted my resignation letter on 15 Aug 2008 and i'm still under probation. My superior had approved my resignation orally on the same date I summitted my resignation letter.
In my letter, it stated that I'm giving a two weeks notice effective from 15 Aug 2008, so that my last service day will be on 29 Aug 2008. All the way, I consider that my superior had approved my resignation. However, after a week, I was informed by HR that she just received my resignation letter from my superoir. I was told that my resignation will only effective from the date approved by my superior which is stated beside her signature. Or else, it is only effective from the date she summitted to HR. Besides, I was also told by the HR pic that my calculation of the 2 weeks notice was wrong, my last day of service suppose is on 30 Aug 2008 because non-working days will be excluded.
So, may I know that when is the actual effective date, the date I summit the letter or the date approved by superior or the date that HR received my letter?
Besides, is the 2 weeks notice excluding the non-working days?
Thanks for your advice.