Additionally, we support ext attribute in CAPS specification which forces us to store many (array) of CAPS nodes for each resource. This attribute (and feature) was deprecated in version 1.4 (2007-08-13), so maybe (just maybe) we should drop support for it 14 years after it was deprecated? That could drop the need for array/collection for each entry kept in memory. I suppose most of the clients were updated already and if not PEP would just not work for them.