summary problem

[Migrated From Jforum.net]

Hi!
I configured the summary to send daily at 21:00.
Some days I receive the message and some days - not
I found out in log file - in the day it success :

Job going to be executed: net.jforum.summary.SummaryJob, null[Sun Jan 14 21:30:00 NZDT 2007]
21:30:00,027 INFO [SummaryModel ] Sending Weekly summary...
21:30:00,549 INFO [SimpleListener ] Job execution ended: net.jforum.summary.SummaryJob, null[Sun Jan 14 21:30:00 NZDT 2007

and in other day (not success):

Job going to be executed: net.jforum.summary.SummaryJob, null[Tue Jan 16 21:30:00 NZDT 2007]
21:30:00,031 WARN [SummaryJob ] com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception:

** BEGIN NESTED EXCEPTION **

java.io.EOFException

STACKTRACE:

java.io.EOFException
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1905)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2351)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2862)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1571)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1666)
at com.mysql.jdbc.Connection.execSQL(Connection.java:2994)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:936)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1030)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at net.jforum.dao.generic.GenericSummaryDAO.listRecipients(GenericSummaryDAO.java:118)
at net.jforum.summary.SummaryModel.listRecipients(SummaryModel.java:112)
at net.jforum.summary.SummaryJob.execute(SummaryJob.java:66)
at org.quartz.core.JobRunShell.run(JobRunShell.java:195)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
** END NESTED EXCEPTION **
Last packet sent to the server was 2 ms ago.
21:30:00,031 INFO [SimpleListener ] Job execution ended: net.jforum.summary.SummaryJob, null[Tue Jan 16 21:30:00 NZDT 2007]

What can be a reason of this exception and how can I solve it?
Thank you

[originally posted on jforum.net by yanam]