We have configured Jenkins to run with Java 1.7 JDK but run our build with IBM Java (1.6)

00:03:38.459 [Release] $ /opt/build/tools/jdk/java-1.6-pxa6460_26sr2fp1-20120622_01/bin/java -Xmx2048m -XX:MaxPermSize=1024m -cp /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven31-agent-1.6.jar:/opt/build/tools/apache-maven-3.1.1/boot/plexus-classworlds-2.5.1.jar:/opt/build/tools/apache-maven-3.1.1/conf/logging jenkins.maven3.agent.Maven31Main /opt/build/tools/apache-maven-3.1.1 /opt/build/jenkins/war/WEB-INF/lib/remoting-2.51.jar /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven31-interceptor-1.6.jar /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven3-interceptor-commons-1.6.jar 38701
00:03:39.181 <===[JENKINS REMOTING CAPACITY]===>channel started
*00:03:40.315 ERROR: JENKINS-18403 JDK 5 not supported to run Maven; retrying with slave Java and setting compile/test properties to point to /opt/build/tools/jdk/java-1.6-pxa6460_26sr2fp1-20120622_01*00:03:40.315 [Release] $ /opt/build/tools/jdk/jdk-1.7.0_60/jre/bin/java -Xmx2048m -XX:MaxPermSize=1024m -cp /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven31-agent-1.6.jar:/opt/build/tools/apache-maven-3.1.1/boot/plexus-classworlds-2.5.1.jar:/opt/build/tools/apache-maven-3.1.1/conf/logging jenkins.maven3.agent.Maven31Main /opt/build/tools/apache-maven-3.1.1 /opt/build/jenkins/war/WEB-INF/lib/remoting-2.51.jar /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven31-interceptor-1.6.jar /opt/build/jenkins/plugins/maven-plugin/WEB-INF/lib/maven3-interceptor-commons-1.6.jar 52333
00:03:41.025 <===[JENKINS REMOTING CAPACITY]===>channel started
00:03:42.778 using settings config with name nexus-nxccbd01
00:03:45.723 Executing Maven: -B -f /release/pom.xml -Dmaven.repo.local=/release/.repository -s /tmp/settings1945838439514897012.xml -T4.0 --fail-at-end -U clean deploy

But it looks like the build is now being run with Java 1.7 instead which is not working.