Clicking the "Disable Roles" checkbox should immediately hide/reveal the role configuration fields

When using IE 8, clicking the "Disable Roles" checkbox does not immediately hide/reveal the role configuration fields.

To reproduce:

1. Open the Crowd Admin Console using IE 8.
2. Go to "Directories" and open an LDAP directory connector.
3. Go to the "Configuration" tab.
4. Remove the tick from the "Disable Roles" checkbox — nothing happens. You have to click the "Update" button or tab out of the field, then the role config fields appear. Similarly, the fields should disappear if you put a tick into the "Disable Roles" checkbox.

(In Firefox 3, the role config fields are immediately revealed when you untick the "Disable Roles" checkbox, and the fields are immediately hidden when you tick the "Disable Roles" checkbox. This is the expected behaviour.)