I now got up and running Bioclipse (2.2) on Eclipse 3.5 :)
I had problems first when just copying the old worspace (Bioclipse 2.0 for Eclipse 3.4), but it was just because I had forgot to upgrade the Bioclipse code base. So I did it, with the command:
Bioclipse now runs on Eclipse 3.5, so time to grab it. I grabbed Eclipse "classic".
I then just opened the workspace that I had prepared earlier by following the instructions at http://wiki.bioclipse.net/index.php?title=Checking_out_Bioclipse_2.0, in Eclipses 3.5 and tried to run Bioclipse 2.2.
It "almost" started... Errors are documented in the attached log file and screenshot.