Strange JDBC issue

Hello,

This seems to be happening intermittently, and once it happens it happens
repeatedly until the JVM is restarted - suggests not a data issue?

Stacktrace (unfortunately truncated to the right):

null


com.ibm.as400.access.JDServerRow.isInput(JDServerRow.java:840)
com.ibm.as400.access.AS400JDBCPreparedStatement.setValue
(AS400JDBCPrepar
com.ibm.as400.access.AS400JDBCPreparedStatement.setString(AS400JDBCPrepa

com.internationalpresence.impscloudgateway.dcfreader.DCFReader.loadFiles

Here is the Java code:

String sql = (
"UPDATE "+lib+".RTGI SET RIRT=?, RIDRV=?, RITL=?, RIX7=? where TELEX = " +
"(select min(telex) from "+lib+".RTGIR where RIURG=? and (RISPR3='' or
RISPR3 is null) and (RIRT is null or RIRT='' or
(RIX7='Cld"+MessageStatus.RETRYING.getCode()+"' and
RIRT='"+MessageStatus.RETRYING.getCode()+"')) "+
whereClause+")");
stmt = StatementManager.prepareStatement(conn, sql);
for (int xPriority=0; xPriority <
DriverConfig.getDriverConfig().getMinimumPriority()+1; xPriority++) {
stmt.setString (1, MessageStatus.WAITING_FOR_RESOURCE.getCode());
stmt.setString (2, CloudQ.getDriverId());
stmt.setString (3, ritsFormat.format(checkingTime));
stmt.setString (4, MessageStatus.WAITING_FOR_RESOURCE.getRIX7Code());
stmt.setInt (5, xPriority);
int records = stmt.executeUpdate();
stmt.clearParameters();
if (records == 1) {
break;
}
}

Highlighted line is the one that breaks - but this is a constant so can't
be null.

Any thoughts?

Many thanks for any input and hope you all have a great weekend.