This is NOT a know issue, when you ask a foreigner wife married to a Malaysian, everyone is shock to hear that the wife is actually not a Permanent Resident. It is very sad because there are a lot of issue rise when the wife could not obtain a permanent resident.
Foreign wife are not allowed to work for the first 5 years of marriage, unless the company goes through a process which takes around 3 months approval. Or when the company has MSC status, they could make the process easier. Even after 5 years, the foreigner will have to obtain a letter from the company to get approval from Immigration.
For example, when your children is born, they are a citizen of Malaysia but not the wife, unless they are approved. If anything happens to the husband (touch wood), the wife will be deported back to their original country, but the child is a citizen of Malaysia.
How long can you get your IC? This is the question arise because there is never a definate answer. Immigration officers will inform you that the application starts after year 5 of marriage.
Why does this issue arise? Does Malaysia government just hate foreigners staying permanent in Malaysia? or there is too many people who hires agent to get a wife from an undevelop country? Is this a race issue affraid that other race will be larger?
UPDATE: This was the case previously, good news for those who are tying the knot now as you can work immediately with the company registration information and a official offer letter from the Company. Head to immigration to get your working permit stamp on your spouse visa.