Oh Sorry i forget to mention my ZS Versions.
Both ends are Using the newest Version of ZS (3.3.1) with 64bit Kernel (ID 49030) and Firmware update (ID 40300).
So that is a bug even in the newest version and not only in older releases.
Is your script also functioning in the newest release?
When yes than i will try it to solve this problem. I hope it solve my Problem.