All the info I could find about the game still list ION Storm as the developer. But as far as I know ION Storm is dead, right? The website is still up, but the last news is from June, just before it was announced that they would be closed down.
http://gamespot.com/gamespot/filters/products/0,11114,528588,00.html
http://pc.ign.com/games/15304.html
http://gamespot.com/gamespot/filters/products/0,11114,528588,00.html
http://pc.ign.com/games/15304.html