Install
1. install java 1.5 from oracle
2. start WAS install: 
    cd /********/Downloads/was.cd.6100.trial.base.linux.ia32/WAS/
    /********/apps/opt/java/jdk1.5.0_22/bin/java -jar setup.jar
3. WAS install window should start ...

Configuration
export JAVA_HOME=/********/apps/opt/java/jdk1.5.0_22
export PATH="/********/apps/opt/java/jdk1.5.0_22/bin:$PATH"
cd /********/apps/opt/WebSphere/AppServer/bin
mv /********/apps/opt/WebSphere/AppServer/java/bin/java /********/apps/opt/WebSphere/AppServer/java/bin/java1
ln -s $JAVA_HOME/bin/java /********/apps/opt/WebSphere/AppServer/java/bin/java
./manageprofiles.sh help -> this should work now!