For clarity, I only "hacked" http://soft.bt747.org/BT747_J2SE_Latest_rxtx2_2p2.jnlp and http://soft.bt747.org/BT747_J2SE_Latest_RXTX2.2_Install.jnlp .According to me the issue is related to a bug in the Ubuntu Java Web Starter following a code change as hinted by a link in one of the previous posts.
I know about the liveCD and I also have a 'Wubi' installation. Virtualbox is running fast on my machine. Because memory is usually a bottleneck for me, I installed 8 GB of it and I can easily allocate a gigabyte to a Virtualbox machine. I did not measure - but there is barely a difference running that 'natively'.Using the liveCD would actually take more time as I need to reboot my machine to get in Ubuntu - I would not have my development environment in that case.
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