Although the Employment Act does not cover non-manual employees with salary more than 1.5K, you can still use the OT rates in this Act as a guidelines for overtime payment. It is not unlawful if employer does not want to follow.
KL Siew has put up a sister site by the name of mylabourlaw.net, which is in effect a more user-friendly version of the present popular pesaraonline.net. The site is in the process of being fine-tuned but it is fully functional. You are invited to visit the website at http://www.mylabourlaw.net and give your views or suggestions. Queries can be posted and be responded from there as usual.