This file is generated by Eclipse if you modify pages.xml or faces-config.xml.
The infinite loop error is a known issue under Jboss 5.1, when eclipse generates these *.spdia files.
So, when you modify the above files, you just delete the generated spdia files. It is the solution. :)
And the purpose of this file is related to the visual displaying of xml files.
Hmm, so I guess the only way to get rid of this problem is to modify the ant build script to delete this file in case it exists... Ok, thank's a lot. I was only afraid that this file might actually have some relevance at runtime and deleting it might cause some problems.
Deleting these files will not cause problems based on my experiences.