no python actions

I have been using blender for about three months now, and i am very impressed with what i am able to do with it. however, one day i turned on my laptop and found that none of the python actions were there. for example: file-> import-> .3ds …
there used to be a variety of options there, with little pythons next to them. now there are only three, without the pythons (stl, dxf, vrml 1.0) i made sure my python was up to date (ie. python version 2.5.2) and it was. the blender prompt tells me that it “got” python. how can i get these options back?