Deposits on Sales Orders

We are looking for a solution to a huge problem. 

We have certain categories of products that require a 50% deposit when placing the order either on the phone or on-line.

The problem is the on-line orders.  We know how to "Accept a customer payment" for a sales order.

When the customer places an order on-line and enter the credit card info, they assume, we "charge" them the 50% deposit when in fact all we do is "authorize" a 100% of the order value.

This has created quite a customer service issue as our B2C customers think they have paid for their order.  When the order arrives 3 months later, we call to get their credit card information "again" and have to explain to them the "authorization" vs. "charging" process.  The customer then has to go back and look for the transaction in their credit card statement (or bank statement if a debit card was used) to satisfy themselves we aren't trying to double bill them.