safe to drive in limp mode?

I believe my 96 jetta is in limp mode. It won't go into overdrive and CEL is on(when isn't it, hehe). How long is it safe to drive in this condition. I commute 12 miles to work every day and on the interstate. But driving 65 without overdrive puts the rpms at about 4500-5000. Is that bad for the engine to rev so high. Besides the poor gas milage will driving at those rpms damage the engine!!!!! I will eventually need to get it looked at but my nearest vw dealer is 45 miles away. So until then, should I continue to drive the car (maybe keep it under 55 miles per hour) or will I ruin something if I don't get it looked at sooner?
Any guidance would be helpful!!

As long as it is a trans problem & not a problem with the engine you won't hurt the engine, since theres something wrong with it the tranny may be hurt by continuing to drive with a problem. The engines can handle that RPM without too much trouble, just make sure it doesn't get too hot.

Ok, thanks for the info. Just what I needed to know. Perhaps I should go get the CEL scanned for codes and see if the problem is with the tranny or what....

Thanks again...

Since it's OBD-II mst Advanced Auto or Autozones will scan it for free or loan you the scanner.