This Problem is fixed in Version 5.06.10 (and above). But you can still use wine to run the Windows Version if you like.

old message:
We experience some problems with the native linux version. Especially the Drag and Drop function to move around reservations does not work as expected.
We are working on a solution.

If you need the Drag and Drop function you can install wine and use the windows version of DormBook on Linux:

To install wine on ubuntu run this command in an terminal

sudo aptitude install wine1.2

then download the windows version of Dormbook to your Desktop and run this command in a terminal

wine DormBook5_windows.exe

to start DormBook you need to run this command:

wine c\:/Programme/DormBook5/DormBook5.exe