I'm looking to remove old quotes from the database via a Magento shell script, and I see enterprise_customer_sales_flat_quote and enterprise_customer_sales_flat_quote_address whose purpose is unclear to me. These are don't have any key constraint on them to the native Mage tables.

In the Enterprise_Customer module, under which the models for these tables are, there is not much responsible code. What are these for, and are they safe to remove along with the "associated" sales_flat_quote/_address records? ("associated" because there is no formal constraint but they seem to have the same entity_ids.