The Juniper NetConnect only works with 32-bits JRE. In order to load NetConnect in 64-bits platform you have install 32-bits JRE.

sudo apt-get install openjdk-7-jre icedtea-7-plugin
sudo apt-get install openjdk-7-jre:i386
sudo ln -s /usr/bin/update-alternatives /usr/sbin/

Here is the reference at this topic: Juniper setup on 12.04