PHP Error: required kolabformat module

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I am using OpenBSD 5.3 and I want to use kolab tasklist. Unfortunately things are not working and just getting the following erro

PHP Error: required kolabformat module not found (GET /mail/?_task=mail&_mbox=INBOX&_folderlist=1&_list=1&_quota=1&_action=refresh&_remote=1&_unlock=loading1385390713816&_=1385390713816)

Ant one with and idea will help.