Looks like a good week for resurrections.
The EM250 architecture is practically identical to the Bluecore (and the block diagram is lot more accurate than the Bluecore literature). It lacks the USB controller, so we'd need to use the UART or debugger interface to control it. However, I'm at the stage where I'm considering doing that with the Bluecore as well.
You mentioned the IDE - is it freely available, or do you have a personal copy? It should be trivial to get it to work with either chipset.
Barry: on the Bluecore, we can use HCI extensions to get our own code running from RAM. One of my current goals is to build a proper toolchain for it. I think this is easily achievable with a few hands.