dovecot-sieve help

hi, I have a question hope to get everybody's help, thank you. I write the dovecot sieve rules, use notify:mailto. such as mailto:mymail@dovecot.org, this is ok.but i want to go to a url address,like this,mailto:"http://http://wiki.dovecot.org/".but i don't know how to do it.I hope you can help me.thanks.