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action,featuresettings2
And you have no third-party SEF component installed?If you look in your includes folder, there is a file named sef.php. Can you paste here any lines with "strtolower" in them?
'featuresettings2' => array('ModSettings.php', 'ModifyFeatureSettings2'),
Also, this does not happen only when editing admin options.It happens on other locations, for instance on the VisualWarning mod.I must find out where the code is changed to lower case. (and why only to me?)
$nqsefurl = substr($nonsefurl, 0, strpos($nonsefurl, 'option')) . preg_replace('/(\;)([^=#]*)([#"])/', '$1$2=$2$3', substr($nonsefurl, strpos($nonsefurl, 'option'), strlen($nonsefurl)));
$nqsefurl = substr($nonsefurl, 0, strpos($nonsefurl, 'option')) . preg_replace('/(\;)([^=#]*)([\;#"])/', '$1$2=$2$3', substr($nonsefurl, strpos($nonsefurl, 'option'), strlen($nonsefurl)));
What happens if you change it to this?