You mean get it translated and authenticated in China embassy in KL? this letter must be authenticated by Chinese embassy there in Malaysia. but I am not sure if they provide translation service.
There is no official notice for this holiday in their web, but generally, the Chinese national holiday is from Oct.1 to Oct 7.

I'm am a ipoh perak, malaysian and my husband is hailin, heilongjiang, china. We got married in China and register malaysia marriage in Malaysia embassy in China BUT if you have no plan to stay in CHINA you are advise to get married in CHINA and get married again in your HOME COUNTRY else it will be very troublesome for your wife/husband to get a long term visa to stay in your home country.

Getting Married in CHINA - The process involve:
1. Apply for your Single Status Declaration Letter from your country embassy in china or go back to your country and apply.
2. Find out where is yours and your China partner federal authority for marriage registration (e.g Hailin, Heilongjiang, China - china marriage with foreigner registration must be done in Harbin and malaysia with heilongjiang marriage registration must be done in Beijing)
3. With your Single Status you and your partner can then get married in the respective china dept.
4. After getting your china marriage booklet, translate them into your homecountry language and have them double certified. Double certification is done by beijing foreign department and your country embassy(you can never get beijing foreign dept thru phone and walk in is not allow, use an agent, they will help send your translated documents into beijing foreign dept and your home country embassy for double certification/verification. (it cost me RMB500 to certified mine by agent)
5. Like i said if you plan to stay in China, after getting your China marriage certificate translated and double certification, go to your own embassy and register your marriage in your home country. ELSE if you plan to bring your partner back to your home country and get married again.

You can have someone else to help submit documents on behalf to save on waiting time.

Malaysia single status declaration comes in English and Chinese. No further translation required.

I just got married July 14, 2010 in Beijing and my husband is China, Chinese.