Not yet, but the good news is that both the ability to customize both the compiler and the debugger are now a reality which means that Helvetia should be much easier to implement.
This should definitely be a topic of high interest.
Is there something similar to Helvetica (http://scg.unibe.ch/research/helvetia) for Pharo 3/4? I'd like to integrate non-ST code into the environment and reuse the existing toolset.