@gpedro as someone said in the forums at bitcointalk, they haven't been updates from the dev in a while, on the progress of that idea.
and yes it's work with sms for what I could read here: http://www.cbronline.com/blogs/technology/just_how_stealt
Pretty good article that shows the flaws that XST have.
I don't say It can't be a great feature for some in the future lol, but no it's not a "feature" Burst has at the moment.
And the "official website" is down:
I leave you with a great quote by someone at BitCoinTalk:
leigh2k14 said:
The key word there is when, all I see here is a load of newbies accounts hyping something that a PnD group/groups has accumulated for 1000 sat.
Until something gets released this ain't worth shit.