In C++ does std::multiset keep a stable sorting order?

Question

Suppose I have two items, a and b, that compare the same. So a < b is false, and b < a is false. If these items are inserted into a std::multiset (or std::multimap) as keys, do I have any guarantees of their final sorted order?

I've checked a couple of references, but I couldn't find the answer. I'm tempted to think that there are no guarantees and that it's left up to each particular implementation.

Thanks.

Answer 1

This thread implies that it is not guaranteed by the current standard but is met by all known current implementations, and gives a link to the C++0x draft standard that includes a guarantee.