will Flash SDK's openMessageDialog support link_href like yml:message??

Hi,
I'm using flash sdk in my project running on yap, and I want to make my app send msg to connections with customized backing url.
But when i saw the source code of YahooSession.openMessageDialog , there is no link_href or link_label like yml:message.
Will it be supported? or is there anyway to call outside js from flash(I want to call the outside script to show the rendered yml:message, but it's cajoled and violate the security constraint!?)? because my app is almost written in AS.