Adding a non existent SecurityPermission to a SecurityPermissionGroup

[Bruno Busco]

Hi,
in the 
https://localhost:8443/webtools/control/EditSecurityGroupPermissionsscreen,
using the Add Permission (manually) to Security Group form, it is
possible to add a non existent SecurityPermission to a
SecurityPermissionGroup.
Is this correct?

Shouldn't any permission always be defined properly in the
SecurityPermission entity before being referenced in a
SecurityPermissionGroup?

Thank you,
Bruno