Hi Andrea,
the problem you are reporting seems to stem from a wrong Java runtime.
I guess you have a 32 Bit Java VM installed but you need 64 Bit Java VM.
We have just put the relevant notes here into the scn for your convenience.
Please have a look onto these two pages:
http://wiki.scn.sap.com/wiki/display/MaxDB/Problems+when+Database+Studio+is+launched
Read here "Assigning the Java runtime environment".
Hope this helps.
Regards,
Barbara