a syntax error,uncaught exception: Syntax error, unrecognized expression: [@href^="mailto:"]

a syntax error,uncaught exception: Syntax error, unrecognized expression: [@href^="mailto:"]

hi, everyone

i'm a newbie on jquery

i'm studying it with the latest version, and following a book called "Learning Jquery"

but i encountered a error, and i don't know what the problem is:

i copied the code from the book like this:
 $('a[@href^="mailto:"]').addClass('mailto');

to try to change the links which start with "mailto" to the new class "mailto"

but there's a error reported:
uncaught exception: Syntax error, unrecognized expression: [@href^="mailto:"]

anyone can tell me how to correct the problem?