It's private property, so you have to follow their rules. However, you can legally store it in your vehicle in their parking lot if it is out of sight and the car is locked. However, I'm not sure if this has actually become law just yet. It was slated to take effect on May 11th last I checked. As far as the law is concerned, you can legally carry at work, but once you are discovered, you will be at the mercy of your employer as to the fate of your job. If you carried a 38 with Federal Hydrashocks in a smart carry holster, you will probably NEVER be "made" at work, lol, unless somebody hides a camera in the bathroom stall; just a thought. heheheh
This thread might help a bit too.