When I tried to create the table including the partitioning clause, I got the following warnings:
Warning 1292 Incorrect datetime value: '0000-00-00'
Warning 1292 Incorrect datetime value: '2010-11-31'
Warning 1292 Incorrect datetime value: '2011-11-31'
After correcting the non existent dates (x-11-31 -> x-11-30) it will not break on that error.
Since it is LESS THAN I suggest to use the first in every month instead, currently you have ranges that start with the last in every month and end with the second last day in every month.
And also TO_DAYS(TIMESTAMP_column) is not allowed as partitioning function, I suggest using UNIX_TIMESTAMP(open_date) instead or change the column type to DATETIME.
Read more in the manual, start with:
http://dev.mysql.com/doc/refman/5.5/en/partitioning-limitations-functions.html