Another option is to provide the correct JAVA_HOME pointing to your version of Java. On ubuntu when using the packaged OpenJDK 6, you can add:
export JAVA_HOME=/usr/lib/jvm/java-6-openjdk
to the top of the 'funambol' startup script.
This way you can use the normal 64bit Java Runtime
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Other option
Another option is to provide the correct JAVA_HOME pointing to your version of Java.
On ubuntu when using the packaged OpenJDK 6, you can add:
export JAVA_HOME=/usr/lib/jvm/java-6-openjdk
to the top of the 'funambol' startup script.
This way you can use the normal 64bit Java Runtime