from http://www.kallisys.com/newton/rustines/

One of my investigations on the NewtonOS concerned system updates. System updates are software loaded during the boot process. The Newton can have only one system update installed. System updates allow to patch system functions and replace NewtonScript objects. Bugs can therefore be fixed and nearly all behaviors can be implemented.

I finally succeeded in writing my first system update in January, 2000; in fact, it only fixes a small bug discovered by Avi Drissman, which many users (including myself) have never experienced. Indeed, as Carsten Lemmen put it talking about me, "Er ist in erster Linie als Technologiedemonstration ("hurra, ich kann es") geeigent und fixed nur den Dates/Find-Bug."

Avi documented this bug and wrote a patch. On the contrary to this patch, the 710031 system update doesn't use more memory than Apple's previous system udpate (717260), neither on the internal store nor on RAM. However, it only works on MP2x00.