Can I share itunes music with two separate computer users on the same computer using the same itunes account?

I have gone through the insturctions on sharing a folder, but it will not update under both itunes libraries when I download new music? For example, I log in as "User A" and download a song on itunes. I then log into the same computer as "User B" and open itunes and the song is not there, even though the music library is the same shared folder on the computer. I tried downloading the music as "User B" but then I get the error: You do not have enough access privileges for this operation".

Does anyone have any ideas how I can properly and continuously share the same music between accounts? I have to use seperate computer log in accounts because my wife and I have our own calendars, contacts, etc...

Thank you!