Why bidirectional mapping fails with empty relationship

Question

Following are my two related tables

public class VProduct{
    @Id
    @Column(name="product_id")
    private Long productId;
    @OneToMany(mappedBy="vProduct", fetch = FetchType.EAGER, cascade={CascadeType.REMOVE})
    private Set<ProductPan> pans;
}

public class ProductPan {
    @Id
    @Column(name="product_pan_id")
    private Long productPanId;

    @Fetch(FetchMode.JOIN)
    @ManyToOne(optional=true, fetch=FetchType.EAGER)
    @JoinColumn(name="product_id", referencedColumnName = "product_id", insertable = false, updatable = false)  
    private VProduct vProduct;
}

I get the following exception when i try to query the VProduct tabel.

org.hibernate.exception.SQLGrammarException: ERROR: column pans0_.product_pan_id does not exist

What am i doing wrong here ? At the moment ProductPan table is empty. And its not guranteed to have any items for a VProduct. if thats the problem is there any annotation i can add to ignore that null data problem ?

This is the hibernate query and result

14:39:49,994 INFO  [stdout] (http-localhost-127.0.0.1-8080-1) Hibernate: select pans0_.product_id as product3_101_1_, pans0_.product_pan_id as product1_1_, pans0_.product_pan_id as product1_71_0_, pans0_.pan_id as pan2_71_0_, pans0_.product_id as product3_71_0_ from product_pan pans0_ where pans0_.product_id=?
14:39:50,113 WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-localhost-127.0.0.1-8080-1) SQL Error: 0, SQLState: 42703
14:39:50,116 ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-localhost-127.0.0.1-8080-1) ERROR: column pans0_.product_pan_id does not exist