EJB Deployment Error

Hai,
I got this error by deploying my application in Jboss 4.2. I created an entity bean application.



Incomplete Deployment listing:

--- MBeans waiting for other MBeans ---
ObjectName: jboss.j2ee:jar=Book.jar,name=BookBean,service=EJB3
State: NOTYETINSTALLED
I Depend On:
persistence.units:unitName=sample

ObjectName: jboss.j2ee:jar=StrutsEJB.jar,name=StudentBean,serv ice=EJB3
State: NOTYETINSTALLED
I Depend On:
persistence.units:unitName=sample

--- MBEANS THAT ARE THE ROOT CAUSE OF THE PROBLEM ---
ObjectName: persistence.units:unitName=sample
State: NOTYETINSTALLED
Depends On Me:
jboss.j2ee:jar=Book.jar,name=BookBean,service=EJB3
jboss.j2ee:jar=StrutsEJB.jar,name=StudentBean,serv ice=EJB3