Can you post the CREATE TABLE statement (including indexes, keys, FKs)? That might help a bit here.

Just so you know, partitioning a table that has other tables pointing to it via FK can be a real pain because, in order for a column to be unique on such a table, either the partitioning column must be added to the otherwise unique column (which would break it as an FK candidate) or the UNIQUE index on the column can't be "aligned" which would kill the ability to do SWITCHes to move legacy data out of the table quickly.