eSATA and Server 2003

Just got a WD MyBook Home Edition (1 TB) simply because it had the eSATA connection because I want to do my backups to it. Except when I connect the MyBook to my Server 2003 box, it isn’t recognized. According to WD, the Home Edition is not supported for Server 2003, but isn’t eSATA a standard and thus it should work anyway? Any ideas?