Does anyone have experience doing delete using data loader command line?

I am getting the following error when I run my batch file:
2013-01-18 14:45:16,382 INFO  [main] controller.Controller initLog (Controller.java:367) - The log has been initialized
2013-01-18 14:45:16,382 INFO  [main] process.ProcessConfig getBeanFactory (ProcessConfig.java:78) - Loading process configuration from config file: c:\program files (x86)\salesforce.com\apex data loader 23.0\conf\process-conf.xml
2013-01-18 14:45:16,413 INFO  [main] xml.XmlBeanDefinitionReader loadBeanDefinitions (XmlBeanDefinitionReader.java:163) - Loading XML bean definitions from file [c:\program files (x86)\salesforce.com\apex data loader 23.0\conf\process-conf.xml]
2013-01-18 14:45:16,428 INFO  [main] core.CollectionFactory <clinit> (CollectionFactory.java:66) - JDK 1.4+ collections available
2013-01-18 14:45:16,444 INFO  [main] core.CollectionFactory <clinit> (CollectionFactory.java:71) - Commons Collections 3.x available
2013-01-18 14:45:16,475 INFO  [OpenOrderDelete] controller.Controller initConfig (Controller.java:328) - The controller config has been initialized
2013-01-18 14:45:16,475 INFO  [OpenOrderDelete] process.ProcessRunner run (ProcessRunner.java:90) - Initializing process engine
2013-01-18 14:45:16,475 INFO  [OpenOrderDelete] process.ProcessRunner run (ProcessRunner.java:93) - Loading parameters
2013-01-18 14:45:17,021 INFO  [OpenOrderDelete] config.LastRun load (LastRun.java:96) - Last run info will be saved in file: c:\program files (x86)\salesforce.com\apex data loader 23.0\conf\OpenOrderDelete_lastRun.properties
2013-01-18 14:45:17,037 FATAL [main] process.ProcessRunner topLevelError (ProcessRunner.java:211) - Unable to run process OpenOrderDelete
java.lang.RuntimeException: java.lang.IllegalArgumentException: No enum const class com.salesforce.dataloader.action.OperationInfo.Delete
 at com.salesforce.dataloader.process.ProcessRunner.run(ProcessRunner.java:136)
 at com.salesforce.dataloader.process.ProcessRunner.run(ProcessRunner.java:74)
 at com.salesforce.dataloader.process.ProcessRunner.main(ProcessRunner.java:226)
Caused by: java.lang.IllegalArgumentException: No enum const class com.salesforce.dataloader.action.OperationInfo.Delete
 at java.lang.Enum.valueOf(Enum.java:192)
 at com.salesforce.dataloader.config.Config.getEnum(Config.java:441)
 at com.salesforce.dataloader.config.Config.getOperationInfo(Config.java:981)
 at com.salesforce.dataloader.process.ProcessRunner.run(ProcessRunner.java:97)
 ... 2 more