Hi! I notice that other implementations of OAI-PMH servers give an error when setSpec specified doesn't exist. For example: + set=foo on Koha ( <http://catalog.bywatersolutions.com/cgi-bin/koha/oai.pl?verb=ListRecords&from=2010-01-01&set=foo&metadataPrefix=oai_dc> ByWaters <http://catalog.bywatersolutions.com/cgi-bin/koha/oai.pl?verb=ListRecords&from=2010-01-01&set=foo&metadataPrefix=oai_dc> ) <http://catalog.bywatersolutions.com/cgi-bin/koha/oai.pl?verb=ListRecords&from=2010-01-01&set=foo&metadataPrefix=oai_dc> : List records anyway + set=foo on a Greenstone v2.82 <http://digital.bl.fcen.uba.ar/gsdl-282/cgi-bin/oaiserver.cgi?verb=ListRecords&metadataPrefix=oai_dc&set=foo> : Return an error. This behavior is expected? I shuld fill a bug? Cheers, Pablo PS: BTW, with the use of <?xml-stylesheet tag > that response is much nicer than Koha one!