copy messages from phone memory to memory card and vice versa

You cannot copy them because you'll loose either the phone ones, or the MMC's. Whay don't you just select MMC for storing them?

When first selection is donne, the phone made a copy of then from one memory to another.

No, it's not like this. If you have messages stored on MMC and on the phone, they are different. I've tested this many times, on N70, 6630, 6670 and 7610. The messages are not the same.

The first time I do that on my N70, the messages I have on phone memory, had gonne to Card memory, and are the same. For me...