TYPO3 Core

Hi,
after upgrade of Typo3 Version 4.4.x to 4.5.x i got errors like this:

Core: Exception handler (WEB): Uncaught TYPO3 Exception: Parameter Error: Wrong parameters sent. | UnexpectedValueException thrown in file .../typo3_src-4.5.17/typo3/sysext/cms/tslib/showpic.php in line 187

The Error is flooding my Backend and causes performance issues if it happens several times in succession.

I read in the Web about the problem and also given instructions here: http://forge.typo3.org/issues/26893#change-123322 and here:
http://www.typo3forum.net/forum/typo3-4-x-installation-updates/53163-core-exception-handler-web-showpic-php-line-173-a-2.html#post177998

But the answers are no solution for the still existing problem.

If I disable the Error Handling, then the error still occurs and in fact it is possible, that my server is getting to much flooded. Showpic.php is causing performance issues because of this.

Also i tried the given instructions in the forums but after a few days, still nothing changed.

I also do not understand, why this very hard error is marked as solved. That is no solution.

thanks for any help and hope the bug will be fixed.