Hook script with ldap array

According to the documentation ldap array's should be passed automatically to the hook script in the form value1|value2|value3. I'm using a hook posixaccount/postmodify and want to get the arrays "host" and "gosaMailAlternateAdress". I get only the first value of each array passed to the script.

(from redmine: issue id 3468, created on 2014-11-17, closed on 2014-11-24)