[thredds] aggregation opendap error

I'm trying to open an aggregation using opendap ASCII, but I get the following error: 

Error {
    code = 500;
    message = "readAgg SASS/SIO/SIOPier/2012";
};
I'm aggregating each month's netcdf file into a single year. Each nc file is about 1-2 Mbytes. The error only shows up on the 2012 aggregations though and if I try to open each individual netcdf file, I get no error. I'm not sure if it matters, but I have a crontab regenerating the current month's nc file every 4 minutes. 


The log file gives me this:
2012-10-25T10:39:25.700 -0700 [ 251307517][ 196] ERRO2012-10-25T10:39:25.700 -0700 [ 251307517][ 196] ERROR - ucar.nc2.ncml.Aggregation - readAgg SASS/SIO/SIOPier/2012 
ucar.ma2.InvalidRangeException: Bad range ending value at index 0 == 7904
    at ucar.ma2.Index.section(Index.java:240)
    at ucar.ma2.Array.section(Array.java:530)
at ucar.nc2.ncml.AggregationOuterDimension$CacheVar.read(AggregationOuterDimension.java:856) at ucar.nc2.ncml.AggregationOuterDimension.reallyRead(AggregationOuterDimension.java:331) 
    at ucar.nc2.dataset.VariableDS._read(VariableDS.java:496)
    at ucar.nc2.dataset.VariableDS._read(VariableDS.java:520)
    at ucar.nc2.Variable.read(Variable.java:658)
    at ucar.nc2.Variable.read(Variable.java:632)
    at thredds.server.opendap.NcSDArray.read(NcSDArray.java:115)
    at opendap.servlet.AsciiWriter.writeAsc(AsciiWriter.java:95)
    at opendap.servlet.AsciiWriter.toASCII(AsciiWriter.java:56)
at thredds.server.opendap.OpendapServlet.doGetASC(OpendapServlet.java:324) 
    at thredds.server.opendap.OpendapServlet.doGet(OpendapServlet.java:225)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at thredds.servlet.filter.CookieFilter.doFilter(CookieFilter.java:54)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at thredds.servlet.filter.RequestQueryFilter.doFilter(RequestQueryFilter.java:122) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at thredds.servlet.filter.RequestPathFilter.doFilter(RequestPathFilter.java:105) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) 
    at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:200)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) 
    at java.lang.Thread.run(Thread.java:662)
2012-10-25T10:39:25.701 -0700 [ 251307518][ 196] ERROR - thredds.server.opendap.OpendapServlet - path= /SASS/SIO/SIOPier/2012.ascii 
java.lang.IllegalArgumentException: readAgg SASS/SIO/SIOPier/2012
at ucar.nc2.ncml.AggregationOuterDimension.reallyRead(AggregationOuterDimension.java:336) 
    at ucar.nc2.dataset.VariableDS._read(VariableDS.java:496)
    at ucar.nc2.dataset.VariableDS._read(VariableDS.java:520)
    at ucar.nc2.Variable.read(Variable.java:658)
    at ucar.nc2.Variable.read(Variable.java:632)
    at thredds.server.opendap.NcSDArray.read(NcSDArray.java:115)
    at opendap.servlet.AsciiWriter.writeAsc(AsciiWriter.java:95)
    at opendap.servlet.AsciiWriter.toASCII(AsciiWriter.java:56)
at thredds.server.opendap.OpendapServlet.doGetASC(OpendapServlet.java:324) 
    at thredds.server.opendap.OpendapServlet.doGet(OpendapServlet.java:225)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at thredds.servlet.filter.CookieFilter.doFilter(CookieFilter.java:54)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at thredds.servlet.filter.RequestQueryFilter.doFilter(RequestQueryFilter.java:122) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at thredds.servlet.filter.RequestPathFilter.doFilter(RequestPathFilter.java:105) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) 
    at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:200)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) 
    at java.lang.Thread.run(Thread.java:662)
Caused by: ucar.ma2.InvalidRangeException: Bad range ending value at index 0 == 7904 
    at ucar.ma2.Index.section(Index.java:240)
    at ucar.ma2.Array.section(Array.java:530)
at ucar.nc2.ncml.AggregationOuterDimension$CacheVar.read(AggregationOuterDimension.java:856) at ucar.nc2.ncml.AggregationOuterDimension.reallyRead(AggregationOuterDimension.java:331) 
    ... 36 more
2012-10-25T10:39:25.702 -0700 [ 251307519][ 196] INFO - thredds.server.opendap.OpendapServlet - Request Completed - 500 - -1 - 3
The link to the server is at http://sccoos-obs0.ucsd.edu/thredds/catalog-AutomatedShoreStations.html?dataset=SASS/SIO/SIOPier/2012 

Here's a snippet of the catalog file with 2012 and 2011:

    <dataset name="SIO, SIOPier, 2012" ID="SASS/SIO/SIOPier/2012"
             urlPath="SASS/SIO/SIOPier/2012" >
      <metadata inherited="true">
<documentation type="summary">Automated Shore Stations - SIO - SIOPier - 2012</documentation> 
      </metadata>
<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";> <aggregation dimName="datetime" type="joinExisting" recheckEvery="10 min"> 
          <scan location="/data/InSitu/SASS/data/SIO/SIOPier/"
                regExp="SASS\.\w+\.\w+\.2012([0-9]{2})\.dat\.nc$"
                subdirs="false" />
        </aggregation>
      </netcdf>
    </dataset>
    <dataset name="SIO, SIOPier, 2011" ID="SASS/SIO/SIOPier/2011"
             urlPath="SASS/SIO/SIOPier/2011" >
      <metadata inherited="true">
<documentation type="summary">Automated Shore Stations - SIO - SIOPier - 2011</documentation> 
      </metadata>
<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";> <aggregation dimName="datetime" type="joinExisting" recheckEvery="10 min"> 
          <scan location="/data/InSitu/SASS/data/SIO/SIOPier/"
                regExp="SASS\.\w+\.\w+\.2011([0-9]{2})\.dat\.nc$"
                subdirs="false" />
        </aggregation>
      </netcdf>
    </dataset>