You can not add job ERROR

I have a job package that allows to post only one Job. When the user wants to post new (second) job, the system displays the "You can not add job" error message. I understand that this error message is correct, but it would be less confusing and easier for the user if the system would take him to the "Packages" page to choose and buy a new package. How can I set the system to redirect to the "Packages" page or to show a "Buy new package" button instead of giving this error. Users get confused and do not know what to do.