I've had a request for our upper administration to research the cost/possibility
of using SharePoint on Blackberry. Specifically, the administration wants to be
able to edit task (approve leave, etc) from their Blackberries.

Is this possible?

If so, where do I begin to search for solutions? Will a Storm or IPhone be
needed (something touch screen) or does it matter?

Is there additional software or such needed on the SharePoint/SQL server?

We are using MOSS and have 1 sharepoint box and 1 sql server box.

If anyone can point me in the right direction for researching this.