more than one, OneToOne relation gives problem

[thiagu.m]

This is my bean class structure

@Entity
@Table(name="TBL_PRODUCTS")
public class TblProducts implements Serializable
{
 @Id
 @Column(name="PRODUCT_ID")
 private BigDecimal productId;

 @Column(name="PRODUCT_NAME")
 private String productName;

 @JoinColumn(name="BRAND_NAME")
 private String brandname;

 @OneToOne(fetch=FetchType.LAZY,mappedBy="tblProducts")
 private TblCellphone tblCellphone;

 @OneToOne(fetch=FetchType.LAZY,mappedBy="tblProducts")
 private TblTelevision tblTelevision;

}
-------------------------------------------------
@Entity
@Table(name="TBL_CELLPHONE")
public class TblCellphone implements Serializable
{
 @Id
 @Column(name="PRODUCT_ID")
 private BigDecimal productId;

private String camera;

. . .

@OneToOne(optional=false)
 @JoinColumn(name="PRODUCT_ID")
private TblProducts tblProducts;
}
----------------------------------------
@Entity
@Table(name="TBL_TELEVISION")
public class TblTelevision implements Serializable
{
 @Id
 @Column(name="PRODUCT_ID")
 private BigDecimal productId;

 @Column(name="SCREEN_SIZE")
 private String screenSize;

 . . .

 @OneToOne(optional=false)
 @JoinColumn(name="PRODUCT_ID")
 private TblProducts tblProducts;
}

Here Tblproduct is my main table , I need to make a relation with all other subcategory products table.
But when I try to add the more than one OneToOne relation within product table it gives following error

java.lang.NullPointerException at org.hibernate.cfg.OneToOneSecondPass.doSecondPass(OneToOneSecondPass.java:135) at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1130) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:296) at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1115) at org.hibernate.ejb.Ejb3Configuration.buildMappings(Ejb3Configuration.java:1233) at org.hibernate.ejb.EventListenerConfigurator.configure(EventListenerConfigurator.java:154) at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:869) at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:407) at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:126) at org.jboss.ejb3.entity.PersistenceUnitDeployment.start(PersistenceUnitDeployment.java:246) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source)

is there any help how to overcome this problem