There is a game called that, but its not the same, and vastly updated. I am hoping it comes off though. For a retro version, that stays true to the original, look for Xenonauts - there is a beta due soon and an Alpha out now to test.
I have fond memories of the original XCOM but no way would I want to play it again unchanged. Being in my early twenties then I had the time but not now. Saying that the new XCOM by Firaxis (Civilisation etc) does look pretty epic. Saw a lot of footage from PAX last weekend from a live stream http://www.twitch.tv/2k/videos Day 1 purchase for me!