tomcat报的这个异常太古怪了！

15:22:30,359  WARN com.opensymphony.xwork2.ognl.OgnlValueStack:49 - Error setting value
ognl.MethodFailedException: Method "setPwd" failed for object com.sykjw.action.UserAction@1b9808e [java.lang.NoSuchMethodError: java.lang.String.getBytes(Ljava/nio/charset/Charset;)[B]
	................................................

Caused by: java.lang.NoSuchMethodError: java.lang.String.getBytes(Ljava/nio/charset/Charset;)[B
	at person.pursuit.util.MD5.hexString(MD5.java:63)
	at com.sykjw.action.UserAction.setPwd(UserAction.java:459)
	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)
	at ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:850)
	at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1273)
	... 64 more
/-- Encapsulated exception ------------\
java.lang.NoSuchMethodError: java.lang.String.getBytes(Ljava/nio/charset/Charset;)[B
	at person.pursuit.util.MD5.hexString(MD5.java:63)
	at com.sykjw.action.UserAction.setPwd(UserAction.java:459)
	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)
	at ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:850)
	at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1273)
	at ognl.OgnlRuntime.setMethodValue(OgnlRuntime.java:1474)
	at ognl.ObjectPropertyAccessor.setPossibleProperty(ObjectPropertyAccessor.java:85)
	at ognl.ObjectPropertyAccessor.setProperty(ObjectPropertyAccessor.java:162)
	at com.opensymphony.xwork2.ognl.accessor.ObjectAccessor.setProperty(ObjectAccessor.java:28)
	at ognl.OgnlRuntime.setProperty(OgnlRuntime.java:2245)
	at com.opensymphony.xwork2.ognl.accessor.CompoundRootAccessor.setProperty(CompoundRootAccessor.java:50)
	at ognl.OgnlRuntime.setProperty(OgnlRuntime.java:2245)
	at ognl.ASTProperty.setValueBody(ASTProperty.java:127)
	at ognl.SimpleNode.evaluateSetValueBody(SimpleNode.java:220)
	at ognl.SimpleNode.setValue(SimpleNode.java:301)
	at ognl.Ognl.setValue(Ognl.java:737)
	at com.opensymphony.xwork2.ognl.OgnlUtil.setValue(OgnlUtil.java:192)
	at com.opensymphony.xwork2.ognl.OgnlValueStack.setValue(OgnlValueStack.java:155)
	at com.opensymphony.xwork2.ognl.OgnlValueStack.setValue(OgnlValueStack.java:143)
	at com.opensymphony.xwork2.interceptor.ParametersInterceptor.setParameters(ParametersInterceptor.java:273)
	at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:187)
	at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
	at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
	at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
	at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
	at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
	at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
	at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)