Palette problem

Hi;

I try to add my calendar component (.jar) to my palette). Palette manager can detect the components in it but if I add them to palette they have an icon with "?". I cant add these component to my frame. What is the problem? (I have this preblem with other components from internet too)

I use Netbeans or Java Studio Enterprise Ed. 8.1

[357 byte] By [Genomsarena] at [2007-11-27 7:59:23]