calendar suddely showing zend optimizer error message

[srp]

Hello .. hope someone can help me with this asap
My calendar's been on my domain and working just fine for about a month now .. then this morning i wake up and instead of loading the calendar, the error message below loads ... should i be contacting my host company's tech support for this .. just wondering if they made a server change overnight

the error message:
Zend Optimizer not installed

This file was encoded by the Zend Encoder / Zend SafeGuard Suite
In order to run it, please install the freely available Zend Optimizer, version 2.1.0 or later.
What is the Zend Optimizer?

The Zend Optimizer is one of the most popular PHP plugins for performance-improvement, and has been freely available since the early days of PHP 4. It improves performance by taking PHP's intermediate code through multiple Optimization Passes, which replace inefficient code patterns with efficient code blocks. The replacement code blocks perform exactly the same operations as the original code, only faster.
In addition to performance-improvement, the Zend Optimizer also enables PHP to transparently load files encoded by the Zend Encoder or Zend SafeGuard Suite.
The Zend Optimizer is a freely-available product from Zend Technologies. Zend Technologies is the company that develops the scripting engine of PHP, also known as the Zend Engine.

[Brian]

I responded to your ticket:

This can only be caused by a change on the server. Either Zend Optimizer was disabled, outdated, or PHP was upgraded without upgrading the optimizer. You should definitely check with your host to have this resolved.

[srp]

thanks, it was indeed the host .. i dunno what they did, but i contacted them and they seemed to know what they did wrong and fixed it in about 30mins
whew!