interesting bug in IE7 (or feature)

I ran into the not described property of IE7.
in short:
There is a HTML code:

< a href ="1" > </ a >


There is a jQuery design:

$( "a" ).click( function (){
var a = $( this ).attr( "href" );
});

* This source code was highlighted with Source Code Highlighter .

In IE 7, the variable “a” will contain the string

http : // /////1

In all other browsers FF, Opera, Chrome and even IE8 will be the number "1"
On the Internet, as far as I understand, nothing like this has been described ...