java common-lang,Maven包错误：org.apache.commons-lang不存在（Java）

I'm using MyEclipse to develop a really simple Java Struts project. Everything was working fine until I wanted to use the StringUtils class in org.apache.commons.lang. In MyEclipse I imported the package like

import org.apache.commons.lang.StringUtils;

I added the Jar file for commons-lang-2.4 to my build path. This all works fine and dandy and I get the Intellisense and no errors in Eclipse or anything. Now, when I go to do a mvn clean package, I get an error saying that

The package org.apache.commons.lang does not exist

I checked in my war/Pom.xml file and I do have it declared as a dependency

org.apache.httpcomponents

httpclient

4.0.1

commons-lang

commons-lang

2.4

From my research I figured that Maven should download the package and install it to my local repository if it doesn't exists. I checked