Need to setup special Prorate Calendar

I'm trying to setup a Prorate Calendar to meet a requirement that assets with a date placed in service from the 1st to 15th depreciate in the current month and assets placed in service from the 16th to 30/31st depreciate in the following month.  I set up a Fiscal Year calendar with dates like 16-DEC-10 to 15-DEC-11 are for FY 2011, 16-DEC-11 to 15-DEC-12 are for FY 2012 and so on.  Then I set up the Prorate Conventions as 16-DEC-2010 to 15-JAN-2011 have a Prorate Date of 31-JAN-2011; 16-JAN-2011 to 15-FEB-2011 has a prorate date of 28-FEB-2011 and so on.