<b>Mac OS 8.1 and system crashes when quitting applications: Kaleidoscope 1.8.1 and/or Virtual Memory involved?

When running Mac OS 8.1, several readers are reporting a symptom of getting a system crash (most often a Bus Error) whenever they quit an application. A few readers claim that disabling Kaleidoscope 1.8.1 (or even reverting to version 1.8) eliminates the problem.

Based on some comments I received from a source that wishes to remain anonymous, this problem may also disappear if you turn off virtual memory. Here are the details:

It is possible that a non-Apple extension (Kaleidoscope 1.8.1??) is allocating memory in a program's Application heap and still using that memory after the application quits. If so, this is a bug in the extension: it should be allocating its memory to the System heap, not the Application heap.

Before Mac OS 8.1, such a bug could cause random crashes when the memory is reused where the application used to be. However, under Mac OS 8.1, the memory where an application used to be is marked as "garbage" via a new Virtual Memory call and so the "random" crash becomes an "every time" crash.