I mean much stronger than that. Like the big one in a speaker.
Or these.
http://www.stewmac.com/shop/Tools/Sp...r_Magnets.html
Some guys over at the Seymour Duncan Forum use them to degauss the magnets in their pickups. They are MUCH stronger than guitar pickup magnets. They have to be swiped across the pickups magnets with opposing polarity ala N/N or S/S.
Theoretically you could degauss the Jazz' magnet with the super D, but it would take forever.
Don't worry about it, you are fine.