Io exception: Connection refused

Has any one seen similar exceptions to the following one? Why do I get the exception?

Thanks,

Christian

java.sql.SQLException: Io exception: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=153093120)(ERR=12519)(ERROR_STACK=(ERROR=(CODE=12519)(EMFI=4))))

	at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
	at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:179)
	at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:333)
	at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:404)
	at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:468)
	at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:314)
	at java.sql.DriverManager.getConnection(DriverManager.java:512)
	at java.sql.DriverManager.getConnection(DriverManager.java:141)
	at oracle.jdbc.pool.OracleDataSource.getConnection(OracleDataSource.java:169)
	at oracle.jdbc.pool.OracleDataSource.getConnection(OracleDataSource.java:108)
	at com.bristol.tvision.datamgr.OracleDataSourceConnectionSource.getConnection(OracleDataSourceConnectionSource.java:69)
	at com.bristol.tvision.datamgr.DataManager.connect(DataManager.java:1053)
	at com.bristol.tvision.datamgr.DataManager.getThreadConnection(DataManager.java:368)
	at com.bristol.tvision.services.collection.EventQueueThread.run(EventQueueThread.java:97)