Here we describe the molecular identification of a cDNA encoding a novel serine protease we have termed protease EOS. In one aspect, an out-of-process application executing in a separate process from the server program is invoked to process the request and to generate a response to be returned to the client, and the server architecture includes a subsystem to detect when the out-of-process application fails and to recover the out-of-process application without disrupting operation of the server program. Each of the recesses is configured to receive and align one of the modular printer assemblies with the other modular printer assemblies.