DK不兼容异常（class file has wrong version 49.0, should

<2010-4-2 上午08时43分38秒 CST> <[ServletContext(id=33462681,name=example,context-path=/example)] Root cause of ServletException.
weblogic.servlet.jsp.CompilationException: Compilation of C:\bea\user_projects\domains\mydomain\myserver\.wlnotdelete\extract\myserver_example_example\jsp_servlet\__login.java failed.
C:\bea\user_projects\domains\mydomain\myserver\.wlnotdelete\extract\myserver_example_example\jsp_servlet\__login.java:235: cannot access example.struts.form.LoginForm
bad class file: C:\bea\user_projects\domains\mydomain\applications\example\WEB-INF\classes\example\struts\form\LoginForm.class
class file has wrong version 49.0, should be 48.0
Please remove or make sure it appears in the correct subdirectory of the classpath.
          example.struts.form.LoginForm form = null; //[ /login.jsp; Line: 22]
                             ^
1 error

关键语句：

bad class file: .........
class file has wrong version 49.0, should be 48.0  .........
此为JDK不兼容。

 
Eclipse中JDK不兼容异常（class file has wrong version 49.0, should be 48.0）的解决方法
在eclipse 里改变项目的属性设置：[project]->[properties]->[Java Compiler]->选中Enable project specific settings,在JDK Compliance->Compiler compliance level中选1.4（或其它你认为合适的），软件会自动提示需要重新编译，重新编译后运行就ok了。