Inside wdbb.dcl, you can add descriptions for you terminals.
After creating the bb?xx.dwg as Pat suggested, make the changes to the dcl. The best scenerio would be for an easier way for AutoCAD to allow you to modify these areas. Say maybe some kind of Wizard to modify the files. The code area to look for is seen below. As you can see, we use up to 7.
Good luck.
// :popup_list
:list_box
{
height=10;
key="trmtype";
list="0=None (wire conn only)\n1=Screw\n2=Small screw\n3=Circle\n4=Circle, num inside\n5=Square, num inside\n6=Large Connector\n7=Small Connector\n8=\n9=";
}
// :spacer{height=1;}