title: maven does not compile in java 1.6
body: <p>how to force maven to compile 1.6 compatible source</p>
  
  <p>i made web-app project with maven in eclipse. change web.xml to use 3.0 version -> then update configuration and now i cant start tomcat.
  I found that i have to force maven to compile source 1.6 compatible and i have to add</p>
  
  <pre><code>&lt;plugin&gt;
      &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
      &lt;artifactId&gt;maven-compiler-plugin&lt;/artifactId&gt;
   &lt;configuration&gt;
      &lt;source&gt;1.7&lt;/source&gt;
      &lt;target&gt;1.7&lt;/target&gt;
      &lt;showDeprecation&gt;true&lt;/showDeprecation&gt;
      &lt;showWarnings&gt;true&lt;/showWarnings&gt;
      &lt;executable&gt;${env.JAVA_HOME_7}/bin/javac&lt;/executable&gt;
      &lt;fork&gt;true&lt;/fork&gt;
  &lt;/configuration&gt;
  </code></pre>
  
  <p></p>
  
  <p>but effective pom in eclipse is not editable </p>
  
  <p>so is there a maven compatible with eclipse or any other way to force maven to compile source 1.6 version?</p>