[RS_Jelle]

In vBulletin 4.1.3 border-radius was added (http://tracker.vbulletin.com/browse/VBIV-4888), so you don't need to replace it any more. If you run this mod on 4.1.3, you will get two border-radius instances.
+ It only seems to replace the webkit part and it's not removing the mozilla part like it should.

So you get:

.bbcode_quote div.quote_container {
	-moz-border-radius: 5px;
	border-radius: 5px;
	border-radius: 5px;
	padding: 5px 10px 5px 10px;
}