Java Development Tools

hi,

I'm facing an error which says 'Error opening zip file or JAR manifest missing' when i try to run the session bean. I tried my level best to solve the issue but i could not find a proper solution. this error cause me to develop the application 7 times from the scratch. I take the benefit from EJB to develop the application. Error log is presented below,

java version "1.6.0_24"
Java(TM) SE Runtime Environment (build 1.6.0_24-b50)
Java HotSpot(TM) Client VM (build 19.1-b02, mixed mode)
Starting WLS with line:
C:\Oracle\MIDDLE~1\JDK160~1\bin\java -client -Xms256m -Xmx512m -XX:CompileThreshold=8000 -XX:PermSize=128m -XX:MaxPermSize=512m -Dweblogic.Name=DefaultServer -Djava.security.policy=C:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\weblogic.policy -Djavax.net.ssl.trustStore=C:\Users\BOTOEO\AppData\Local\Temp\trustStore440838012585549990.jks -javaagent:../modules/org.eclipse.persistence_1.1.0.0_2-1.jar -Doracle.jdeveloper.adrs=true -Dweblogic.nodemanager.ServiceEnabled=true -Xverify:none -da -Dplatform.home=C:\Oracle\MIDDLE~1\WLSERV~1.3 -Dwls.home=C:\Oracle\MIDDLE~1\WLSERV~1.3\server -Dweblogic.home=C:\Oracle\MIDDLE~1\WLSERV~1.3\server -Djps.app.credential.overwrite.allowed=true -Dcommon.components.home=C:\Oracle\MIDDLE~1\ORACLE~1 -Djrf.version=11.1.1 -Dorg.apache.commons.logging.Log=org.apache.commons.logging.impl.Jdk14Logger -Ddomain.home=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1 -Djrockit.optfile=C:\Oracle\MIDDLE~1\ORACLE~1\modules\oracle.jrf_11.1.1\jrocket_optfile.txt -Doracle.server.config.dir=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\config\FMWCON~1\servers\DefaultServer -Doracle.domain.config.dir=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\config\FMWCON~1 -Digf.arisidbeans.carmlloc=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\config\FMWCON~1\carml -Digf.arisidstack.home=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\config\FMWCON~1\arisidprovider -Doracle.security.jps.config=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\config\fmwconfig\jps-config.xml -Doracle.deployed.app.dir=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\servers\DefaultServer\tmp\_WL_user -Doracle.deployed.app.ext=\- -Dweblogic.alternateTypesDirectory=C:\Oracle\MIDDLE~1\ORACLE~1\modules\oracle.ossoiap_11.1.1,C:\Oracle\MIDDLE~1\ORACLE~1\modules\oracle.oamprovider_11.1.1 -Djava.protocol.handler.pkgs=oracle.mds.net.protocol -Dweblogic.jdbc.remoteEnabled=false -Dwsm.repository.path=C:\Users\BOTOEO\AppData\Roaming\JDEVEL~1\SYSTEM~1.81\DEFAUL~1\oracle\store\gmds -Dweblogic.management.discover=true -Dwlw.iterativeDev= -Dwlw.testConsole= -Dwlw.logErrorsToConsole= -Dweblogic.ext.dirs=C:\Oracle\MIDDLE~1\patch_wls1035\profiles\default\sysext_manifest_classpath;C:\Oracle\MIDDLE~1\patch_jdev1112\profiles\default\sysext_manifest_classpath weblogic.Server
Error occurred during initialization of VM
agent library failed to init: instrument
Error opening zip file or JAR manifest missing : ../modules/org.eclipse.persistence_1.1.0.0_2-1.jar
Process exited.

why am i getting this often? how could i solve this?
I'm using jDeveloper 11 and oracle 10 xe. OS is win 7.