Question: Just wondering if anyone came across to an issue, that jQuery mobile doesn't have a flash error / infor / warning messages.

Is there any 3d party libraries that deal with that messages?

PS. Don't need a popup.

Answer: 
I found ***jquery-message*** project: 

> 
> <http://code.google.com/p/jquery-message/>
> 
> 
> 

But haven't tested yet.
The [mobile demo page](http://jquery-message.googlecode.com/hg/demo/mobile.html) seems like what you are looking for
I'm years late to this thread, but the reason is because jQuery is submitting the form (likely you're submitting a form and want a response) via AJAX, which is async, so the response comes back before the server sets the flash message, and the flash isn't being rendered in the ajax callback.

Long story short, if you set data-ajax="false" on your form, you'll get the flash error / success whatever. But this kinda defeats the purpose of the "mobile-native" feel of jQuery Mobile. I'm facing the same problem with my app...