WSDL periodically unavailable on Glassfish

Periodically our Glassfish 4.1 installation seems to be unable to allow the WSDL for our Web service to be available. When I try to reach it through my browser it gives a "connection was reset" error. The typical stack trace from our java applications that consume the services get when this happens is included below. Any ideas what could be causing this? Thanks!

javax.xml.ws.WebServiceException: Failed to access the WSDL at: http://venus:9090/USProjectServices/LingoAtTaskService?wsdl. It failed with:
Got Unexpected end of file from server while opening stream from http://venus:9090/USProjectServices/LingoAtTaskService?wsdl.
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.tryWithMex(RuntimeWSDLParser.java:173)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:155)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:120)
at com.sun.xml.internal.ws.client.WSServiceDelegate.parseWSDL(WSServiceDelegate.java:260)
at com.sun.xml.internal.ws.client.WSServiceDelegate.(WSServiceDelegate.java:223)
at com.sun.xml.internal.ws.client.WSServiceDelegate.(WSServiceDelegate.java:171)
at com.sun.xml.internal.ws.spi.ProviderImpl.createServiceDelegate(ProviderImpl.java:96)
at javax.xml.ws.Service.(Service.java:77)
at com.lingosys.ws.LingoAtTaskService.(LingoAtTaskService.java:42)
at com.ws.test.Tester1.(Tester1.java:27)
at com.ws.test.Tester1.main(Tester1.java:45)
Caused by: java.io.IOException: Got Unexpected end of file from server while opening stream from http://venus:9090/USProjectServices/LingoAtTaskService?wsdl
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.createReader(RuntimeWSDLParser.java:842)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.resolveWSDL(RuntimeWSDLParser.java:283)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:140)
... 9 more
Caused by: java.net.SocketException: Unexpected end of file from server
at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:718)
at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:579)
at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:715)
at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:579)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1322)
at java.net.URL.openStream(URL.java:1037)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.createReader(RuntimeWSDLParser.java:827)
... 11 more