Hello,
Thanks for your contribution, however I still get the #SYNTAX for both of the solutions you have posted. I am using the BO 4.1 SP1.
On the other hand the dimension [Project Definition. - Key] looks like this:
Do you think this is the problem why I am getting the syntax error message? Or do you have any other idea or solution?
Thanks a lot for your help. Hopefully there is another solution. 
Iliana