sorry for spamming this forum with problems that seem to be very me-specific. it was again a permission problem (at least i think so..). as soon as the var directory is owned by webserver nothing works correctly. i had to change the ownership to the www user.
"as soon as the var directory is owned by webserver nothing works correctly. i had to change the ownership to the www user."
On most systems the webserver runs as "www" user. So imho "www=webserver". Or did you meant as soon as its owned by the webserver everything works correctly?
dear tobias, thanks for the reply and sorry to be so confusing..now my var dir is not owned by www (webserver) anymore, but chmodded 777 (i know, not secure) and owned by me. and it's only now that ev. runs fine. possibly i'm confusing stuff, but i think the cronjob system adds some complexity in ownership/permission stuff, especially on plesk servers, where by default the user is not in in the webserver group and vice versa..