Can/should I pre-create tablespaces for range partitioning?

Hi, I am setting up a database and 5 of the largest tables are to be partitioned.  I am proposing to use one large tablespace for the whole 'data' section of the database as the data is to be stored on a SAN.  With one of the tables I need to partition based on a date (createdate).  My problem is that if I partition based on range, the new partions are not automatically created, whereas if I use interval partitioning this will mean that one of the indexes I have must be a global index, hence if I delete records