I'm using an HTC Evo 4G running Android 2.3.5
I'm unable to post on XenForo 1.2 using the phone's default internet browser.
When I tap on the editor text box, a green line is placed around it for a moment then it goes away. The onscreen keyboard never comes up.
This also happens when I try to use the example editors on the Redactor home page:
Using Mobile Firefox instead of the default browser is a good temporary work around.