Tomcat6 does not start correctly when specifying jdk5

Tomcat6 does not start correctly when specifying jdk5

I have installed tomcat6 on debian 7 using apt-get install tomcat6
tomcat6-admin. It also installed java6. The tomcat service starts up just
fine and I can also restart it:
root@dd:/home/user# service tomcat6 status
[ ok ] Tomcat servlet engine is running with pid 2113.
root@dd:/home/user# service tomcat6 restart
[ ok ] Stopping Tomcat servlet engine: tomcat6.
[ ok ] Starting Tomcat servlet engine: tomcat6.
I can access the admin webpage, deploy etc.
But now I would like to specify that tomcat6 should use java5 instead. I
have downloaded and extracted java5 into:
/opt/jdk1.5.0_22
Based on this guide: http://tomcat.apache.org/tomcat-6.0-doc/RUNNING.txt I
have created a file:
/usr/share/tomcat6/bin/setenv.sh
containing:
JAVA_HOME=/opt/jdk1.5.0_22
After I rebooted the machine I verified that the above java5 was used:
root@dd:/home/user# /usr/share/tomcat6/bin/version.sh
Using CATALINA_BASE: /usr/share/tomcat6
Using CATALINA_HOME: /usr/share/tomcat6
Using CATALINA_TMPDIR: /usr/share/tomcat6/temp
Using JRE_HOME: /opt/jdk1.5.0_22
Using CLASSPATH: /usr/share/tomcat6/bin/bootstrap.jar
Server version: Apache Tomcat/6.0.35
Server built: Jul 18 2013 02:02:46
Server number: 6.0.35.0
OS Name: Linux
OS Version: 3.2.0-4-amd64
Architecture: amd64
JVM Version: 1.5.0_22-b03
JVM Vendor: Sun Microsystems Inc.
But when I try to restart tomcat I get this error:
root@dd:/home/user# service tomcat6 restart
[FAIL] Starting Tomcat servlet engine: tomcat6 failed!
The log says:
Sep 12, 2013 1:04:47 AM org.apache.catalina.core.StandardServer await
SEVERE: StandardServer.await: create[8005]:
java.net.BindException: Address already in use
at java.net.PlainSocketImpl.socketBind(Native Method)
at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:359)
at java.net.ServerSocket.bind(ServerSocket.java:319)
Is this something that can simply be ignored for jdk5 or have I done
something wrong?