How do you make a new subldger accounting rule effective?

For Asset Additions we have created a new rule so that the Cost Center value, from default account, is not included in the Asset Cost account.  This rule is active with the appropriate dating and the seed Additions rule is end dated.  Our new rule is not effective.  The Create Accounting Assets process still creates addition journal entries with the cost center value from the default account.  We are not sure what we are missing.