Can't accept meeting requests from my Blackberry

My company is using Outlook 2003 with Exchange for our email setup, as
well as this we have a Blackberry Enterprise server for our Blackberry
Pearl handhelds.

Whenever a meeting request is sent from outlook to the blackberry we
are unable to accept or decline the meeting request. WHen the
trackball or menu button is pressed only the normal "reply" and
"forward" options are available without any sign of any choices for
the meeting itself.

It seems like the Blackberrys are recognising the requests as emails
and not meeting requests.

Has anyone come across any solutions to fix this, or certain options
that need to be enabled/disabled?

Any help is greatly appreciated