Below written advice from Industrial Ralation Department for my case:
For your information in the case of KC Mathews v. Kumpulan Guthrie Sdn. Bhd  2 MLJ 320 at p.321, Raja Azlan Shah CJ (Malaya), as he then was, quoted with approval in the Federal Court the judgement of Das Gupta Jin Express Newspaper (P) Ltd. v. Labour Court & Another AIR  SC 806. The Federal Court ruled that :
ďif no action is taken by the employer either by way of confirmation or by way of termination, the employee continues to be in service as a probationer even after the probationary period is overĒ
1. From this case it is clear that if you have not received any confirmation letter from your employer then you are still a probationer.
2. However you have to ascertain whether it is a normal practice in your company that an employee is deemed to be confirmed after serving six month of probation period. If this is the procedure then you are a confirm employee. The employer may request you to serve 3 month notice.
3. Depending on your status, if you are a confirmed employee then you will be breaching your Employment Agreement.
4. You can leave earlier than 7 August 2007 provided the employer consent and permission is given to include the balance of your annual leave. Whereby you will have to pay to the employer an indemnity of a sum equal to the amount of wages which would have accrued during the term of such notice.