In general, a "EXCEPTION_ACCESS_VIOLATION" occurs in Windows when a program attempts to modify memory that it does not "own." Think of virtual memory as a stack of paper - your program requested several pages to use for variables, but then some part of the program tries to write to a piece of paper that belongs to, say, Firefox. Windows sees this, and kills the process before it can do so.
This can happen a lot in languages like C and C++ where you work with memory "pointers" a lot directly, in Java not so much. Were you doing running multi-threaded or fiddling with memory specifically? Wherever you're messing with memory, try to use Java's built-in variables and similar, that's why we're using a high-level language, so you don't have problems like this
1.4.2 is two major versions ago, and within the 1.4.2 series, the patch levels went up to... 17? Something like that. So they released 9 patches to the JVM you're running. If you must run 1.4.2, you need to get a 1.4.2_17 JVM package. It may fix whatever bug you're seeing.