One of the systems design principles behind the IDEO in-house collaboration system is to "Take the Road More Travelled". This means building a tool that works, as much as possible, the way people are already used to work.
As IDEO say -
"if a tool requires people to go out of their way to use it, adoption will always be a challenge, no matter how wonderfully designed. Wherever possible, strive to integrate tools into existing work processes -- bring the system to the user rather than the other way around. For example, the IDEO blogging system didn't take off until the team added a program that sends digest emails with new content from the blogs each employee has subscribed to"If people are used to receiving notifications through email, then link your system to email. Don't expect people to develop a new work habit just to be able to share knowledge, because they won't.
As Samuel Johnson famously said, "Mankind has a great aversion to intellectual labour; but even supposing knowledge to be easily attainable, more people would be content to be ignorant than would take even a little trouble to acquire it".
So remove the need to take trouble. Lower the barriers to entry to your Knowledge Management system. Take the road more travelled.