// it is a normal project
// in the menu I found no way to transform it
// but so it worked for me:
// 1. edit the .project file and copy the natueres block
<natures> <nature>org.radrails.rails.ui.railsnature</nature> <nature>org.rubypeople.rdt.core.rubynature</nature> </natures>
// 2. copy the buildSpec block too
// (I'm not sure if this is necessary, I did both and it worked)
<buildSpec> <buildCommand> <name>org.rubypeople.rdt.core.rubybuilder</name> <arguments> </arguments> </buildCommand> </buildSpec>
// 3. restart radrails and
// 4. add a webrick-server to the project
// and you are done