I know this has been discussed on this list before, and I apologize for not just looking through the archives myself -- my excuse is that I'm on the road, due to teach using oXygen in a matter of hours, and all h#!! is breaking loose. I have generated some schemas that oXygen can't use to validate an instance; and, I note, oXygen can't validate them. In both cases it sufferes a stack overflow. I am using the current release and have set -Xmx999M and -Xms64M at the end of my oxygenMac.sh file (which is how I invoked oXygen). The schemas can be found at http://bauman.zapto.org/~syd/temp/temi.rnc http://bauman.zapto.org/~syd/temp/temi.rng I tried to validate the schemas w/o using oXygen. `jing` complained that the version of relaxng.rng that came with oXygen does not have a <start> element, but it says that temi.rng is valid against the relaxng.rnc that came with nxml-mode. `rnv` agrees on both counts. (I've also tried several diffferent combinations of TEI modules to see what would and would not cause a stack overflow, but do not have a definitive answer yet.) Can anyone provide any useful info here?