一个Bean管理（BMP）的实体BEAN编译的问题，关于BEAN返回值类型的问题，请求您的帮助，谢谢！

[iStringTheory]

package mytest;

import javax.ejb.EJBLocalHome;
import javax.ejb.CreateException;
import javax.ejb.FinderException;
import java.util.Collection;

public interface AccountHome
extends EJBLocalHome {
public Account create(String accountID, String ownerName) throws
CreateException;

public Account findByPrimaryKey(AccountPK key) throws FinderException;
^^^^^^^
public Collection findByOwnerName(String name) throws FinderException;

public double getTotalBankValue() throws AccountException;
}

这里的public Account findByPrimaryKey(AccountPK key) throws FinderException;
返回值类型不能为Account么？Account是EJBLocalObject对象，错误信息为：
（开发环境：JBuilder X）
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"EJBModule1.jar": [J2EE:160121]Errors encountered while compiling module 'D:\Documents and Settings\Administrator\jbproject\mystruts\EJBModule1.jar.jar':
"EJBModule1.jar": In EJB Account, the home interface findByPrimaryKey method parameter must be the primary key type or java.lang.Object: findByPrimaryKey(mytest.AccountPK)
"EJBModule1.jar": In EJB Account, the finder ejbFindByPrimaryKey(mytest.AccountPK) returned an unexpected type. Finders in the bean class must return the primary key type, java.util.Collection, or java.util.Enumeration


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请大家指教，谢谢！！