What is wrong with the OJS Schema?

Since I was testing the IFIP Digital Library OAI interface, I thought I might as well test the one for the ACS Digital Library and register it with the Open Archives Initiative - Repository Explorer, so researchers could use it as an example of a working system. But it failed the XML Schema validation test. This was the only test failed, but is an important one and is a bit odd, as the archive seems to be working okay. Any one any thoughts?

	Open Archives Initiative - Repository Explorer
	explorer version - 1.46c : protocol version - 2.0 : December 2006

Open Archives Initiative :: Protocol for Metadata Harvesting v2.0
RE Protocol Tester 1.46c :: UCT AIM :: December 2006

(1) Testing : Identify
URL : http://dl.acs.org.au/index.php/index/oai?verb=Identify
Test Result : OK
---- [ Repository Name = ACS Digital Library ]
---- [ Protocol Version = 2.0 ]
---- [ Base URL = http://dl.acs.org.au/index.php/index/oai ]
---- [ Admin Email = dl@tomw.net.au ]
---- [ Granularity = YYYY-MM-DDThh:mm:ssZ ]
---- [ Earliest Datestamp = 2006-12-05T00:40:05Z ]

(2) Testing : Identify (illegal_parameter)
URL : http://dl.acs.org.au/index.php/index/oai?verb=Identify&test=test
Test Result : OK

(3) Testing : ListMetadataFormats
URL : http://dl.acs.org.au/index.php/index/oai?verb=ListMetadataFormats
Test Result : OK
---- [ Only oai_dc supported ]

(4) Testing : ListSets
URL : http://dl.acs.org.au/index.php/index/oai?verb=ListSets
------ Response from Xerces Schema Validation ------
[Error] re.51bDjv:164:37: cvc-pattern-valid: Value 'crpit:Volume 1' is not facet-valid with respect to pattern '([A-Za-z0-9\-_\.!~\*'\(\)])+(:[A-Za-z0-9\-_\.!~\*'\(\)]+)*' for type 'setSpecType'.
[Error] re.51bDjv:164:37: cvc-type.3.1.3: The value 'crpit:Volume 1' of element 'setSpec' is not valid.
/tmp/re.51bDjv: 1632;20;0 ms (76 elems, 52 attrs, 0 spaces, 897 chars)
------- End of Xerces Schema Validation Report  -------
------ Start of XML Response ------

 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/
  http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd">
 2008-08-17T01:32:59Z
 http://dl.acs.org.au/index.php/index/oai
 
  
   ajis
   Australasian Journal of Information Systems
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:ED
   Editorial
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:FT
   AJIS Featured Theme
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:ART
   Articles
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:FTA
   AJIS Featured Theme
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:FTB
   AJIS Featured Theme
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   ajis:FTC
   AJIS Featured Theme
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   jrpit
   Journal of Research and Practice in Information Technology
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   jrpit:ART
   Articles
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   crpit
   Conferences in Research and Practice in Information Technology
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   crpit:ART
   Articles
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
  
   crpit:Volume 1
   Volume 1
   
         xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/"
     xmlns:dc="http://purl.org/dc/elements/1.1/"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/
      http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
     
    
   
  
 


------- End of XML Response -------
Test Result : FAIL!
**** [ERROR] XML Schema validation failed ...

From: "Open Archives Initiative - Repository Explorer" test of
ACS DL, explorer version - 1.46c : protocol version - 2.0 : December
2006 (run 17 August 2008)