Off topic but Patchou you really need to do something about the GUI for the Event Viewer - Details window... it just suxor
A nice little image along the top would be nice... Guido step on it
Now back on topic, The reason your AM/PM text is not showing is because you have made your Scroll Bars larger then what they should be.
To Change it do the following.
Click Start
Click Run
Type control panel and hit enter
Double Click Display
Click the Appearance Tab
Click the Advanced Button
Drop Down the list and choose Scrollbar
Change the size to 16 and you will be fine!