[Owncloud] Sharing contacts and agenda between imap authenticated users

[Johan Hendriks]

Hello all.
I really like owncloud, but one thing i can not seem to get working is 
sharing agenda and or contacts between users authenticated using the 
user_imap plugin.
Is this due the fact that they are not known by owncloud it self?
If so is there a way to get this working or am i chasing rabbits with this?

regards
Johan