I had the same problem and solved by adding:
<argLine>-Xmx1024m -XX:MaxPermSize=256m</argLine>
The whole plugin element is:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<forkCount>3</forkCount>
<reuseForks>true</reuseForks>
<argLine>-Xmx1024m -XX:MaxPermSize=256m</argLine>
</configuration>
</plugin>