Well, I remoted into one of my systems, and I think I was able to reproduce this on 3.318.
I added two Lamp modules, calling them E1 and E2.
I created a simple macro that simply turned them both on.
When I ran it, the commands ran one at a time (based on the activity log).
Next, I changed both lamps to "Old" lamps.
The same thing happened (although the commands did change from the Extended ones to the "%Dim" ones).
That's enough proof for me. I'll add it to the list, and let the developers know that the bug is on the list.
If anyone wants to test further, and try to find a fix for this, feel free.
--Noam