在tomcat 7.0.59版本下，java打得war包依賴了service api的包，然後tomcat啟動報了下面的錯，導致應用啟動失敗，訪問不了。

Mar 20, 2015 11:29:09 PM org.apache.catalina.loader.WebappClassLoader validateJarFile
INFO: validateJarFile(/home/ubuntu/apache-tomcat-7.0.59/webapps/jiagoushi/WEB-INF/lib/servlet-api-3.0-alpha-1.jar) - jar not loaded. See Servlet Spec 3.0, section 10.7.2. Offending class: javax/servlet/Servlet.class
 

		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>servlet-api</artifactId>
			<version>3.0-alpha-1</version>
		</dependency>