Validating mailing addresses

Hi list, I've been looking at a variety of software packages which allow you to validate U.S. mailing addresses against the USPS's database. Unfortunately, all of the products I've been able to find so far are Windows based and only support interfacing via COM. I want to be able to validate and clean up addresses via my PHP application so going with a product with only a COM interface is not going to be sufficient since we're running Linux servers. (Or, is there a trick to calling COM objects from Linux?) Does anyone have any recommendations? The main objective here is to be able to validate mailing addresses and clean them up (if necessary) in order to be able to ship out packages optimally with as few errors as possible. Thanks in advance! Joshua Hoover