Is another process listening on port 443 ?
or, if you dont know, try to use a different port.
see:
KB18175-BlackBerry Administration Service console is not accessible due to a port conflict with other software
dont know if I should recommend to update to 5.0.3. Maybe, better not, because currently everything runs, and you are able to use it. But upgrading something which is partially broken seems not a good advice, unless there is a KB at RIM which knows about this problem and recommends an upgrade to a 5.0.3