How can I read Exchange 2003 email on a Mac with Outlook 2011?
Outlook 2011 can also connect to POP and IMAP accounts, so if your Exchange implementation supports those (IMAP preferred over POP) you should be able to use OL.  Of course, that's not a 'true' Exchange client setup.

Likely better to use your company's Outlook Web Access (OWA), or acquire Entourage 2008.