WD10EARS Hot Swap Problem

I have a WD10EARS and I sometimes have problems hot swapping the drive.

I using a Asus P5Q Pro (latest BIOS installed) and a Thermaltake ST0005U dock. They are connected via eSATA.

When I install the WD10EARS into the dock while Windows 7 is on, I sometimes have to search for New Devices to get it to work. Sometimes this doesnt work as well. I also use a WD1600BEAS and WD1600JD on this dock with no problems. I turn on the dock and Windows 7 instantly sees the drives.

Did I recieve a faulty WD10EARS or is it not designed to be hot swappable?