This solution is written in Clojure and has two main parts:

src/loneclojurian/ovm.clj - a VM implementation
src/loneclojurian/sim.clj - sim-related functions

To run this solution you need a unix-like OS with bash and Java 1.6
(1.5 might work, haven't tried).

In this directory just run:

./bin/clj problem1.clj

And wait. :)

The VM is quite slow, it needs around 30 seconds for one task.

When all the tasks are finished the solutions can be found in the
solutions directory.