In VisualWorks 7.8, I have to turn off atomic loading in order to load the package GbcManagement. If I didn't, the load crashed with a memory overflow.
After tracing down the problem, I found that the load itself actually worked fine. It was the step right afterward that did a purgeUnusedBindings that was failing - specifically in a method called relinkSystem. The relinkSystem method looped through allInstances of DeferredBinding. Maybe it was hitting an object that was garbage but hadn't yet been garbage collected. So, I added a call to do a garbage collect just before the allInstances. That did the trick. GbcManagement loads perfectly every time now.
It goes to show that you have to be careful with allInstances.