sync default calendar with calendar from another user's mailbox
 

I have full read/write access to a shared calendar from my colleague's mailbox in outlook 2003 (exchange).

I am trying to find a way to sunchronise this with my own default calendar as I have my account set up on my android phone and would like to see the appointments on the shared diary. My phone doesn't allow more than one exchange account to be set up.

I work for the NHS so I won't be able to use any 3rd party software, just excel or VBA code.

Any ideas?