merten the errors are due to a bug in our mod_security configuration. They shouldn't be causing any problems other than a bit of noise in your logs.
If the log entries are presenting a problem for you then you can suppress them by disabling mod_security by adding the following to your app's .htaccess
:
<IfModule mod_security.c>
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>
This will turn off the mod_security application firewall for that application which will eliminate the errors in your logs.