It may take a while for the IT department to come to terms with the technology, especially if in the past they have not had to manage the company communications systems. However, given time it is relatively simple to learn, certainly no harder than adding a new piece of equipment or network attached appliance. Some vendors claim VoIP can seamless be integrated with your existing network cabling and infrastructure -- just plug in the gateway and the phones to your network and Bob's your uncle.
Ah the number of times we've heard that marketing hype in the IT industry...
I apologise in advance to all the over-worked company technicians and technical departments for having them lumped with learning and implementing another system to support, but once it is in place they will also benefit from its features, don't forget that you will have the ability to route voice messages just like e-mail messages so long live the technical query handball!