Work around? Exchange 2003 w/iPhone, MacBook, Office 2011

I serve as an elected official for a small city.

Most of the City's desktops are PC's; the City has about 50-50 iPhones and Blackberry's. This year, budget cuts are draconian. We're stuck; it will be years and years before we have the resources to update from Exchange 2003, Windows XP, and Office 2003 and PC's of a similar age.

In order to comply with the Washington State Open Records Act, my official email and calendar must remain on the City's Exchange 2003 server. (I can sync or mirror,but I can't move to a different server.)

I use my own (2010) MacBook (10.6.5) and a 3G iPhone (4.2.1); and, I have personal accounts both on MobieMe, and gmail.

I am looking for a way to keep my email and calendar from Exchange 2003 Server synchronized on my MacBook and my iPhone (latencies of 5 or so minutes are acceptable, 60 minutes is not.)