When i wanna use the ':not' selector (eg sample below), it doesn't work.

I must use the '.not()' function to have the same results.

Sample (1.2.6 -> Working / 1.3 -> Doesn't work anymore):

alert( $('ul').find('li:not(li:first)').length );

Sample (1.2.6 , 1.3 -> Working):

alert( $('ul').find('li').not('li:first').length );