Synchronizing Exchange 2003 with a SQL server database

Objective: Connecting and synchronizing between Exchange 2003 and an online back office with a SQL server database The difficulty is that our MS SQL Server database uses a different structure as the Exchange server 2003 database. The contacts structure is the main problem. We are using two tables to store main contact details. A table for the user details and a table for the company of the user. The company of a user is linked by company ID in the table users. In Exchange this structure is totally different. Also within the back office system db it is not allowed that there is no company connected to an user. So the company ID may never be empty. This is possible within exchange/outlook. Because we use one database for multiple back office clients, its essential that when Exchange 2003 and the Back office synchronizes the back office ID is insert in the table to identify in which contact list the contact is belonging. We also want that the user needs to login once. Now we have a login for the back office and Exchange. I am not willing to change the whole back office database structure…so I hope some one can come with an easy and good solution. This are the needs: [login to view URL] our Microsoft SQL server db of the back office to the Exchange server. [login to view URL] information between the databases without changing the whole database structure of the back office. [login to view URL] data inserted with outlook to the correct client/ back office in the back office system and visa versa. [login to view URL] once. 5.A quick solution to get thing working asap. Please put in your proposal only clear solutions...and dont come with only the text "We can do it" ;)