-XX:MaxPermSize=256m

<configuration>
  <systemProperties>
    <XX:MaxPermSize>256m</XX:MaxPermSize>
  </systemProperties>
</configuration>

MAVEN_OPTS=-XX:MaxPermSize=256m

<configuration>
  <systemProperties>
    <JAVA_OPTS>-Xms256m -Xmx512m -XX:MaxPermSize=256m</JAVA_OPTS>
  </systemProperties>
</configuration>