Hello all - I've been trying to track down this small but annoying issue. We've got a logging utility built up that builds XML documents during our test executions. We've written a handful of matlab helper functions that wrap Java XML code for doing things like adding text elements, etc.. We've been able to produce some nice documents, but randomly the string "null" appears at the command line output. I have not been able to trace what is causing this output. I imagine its something in Java, because matlab doesn't really have the concept of "null", and I've grepped our entire source and "null" never appears. The trouble is, it is not repeatable. It happens just enough to stay on my radar. Are there techniques to trap the command line output of Java code running in matlab? I am hoping there's some way I can cause a breakpoint whenever "null" is printed to the command line.