What version of jQuery Mobile?
If this is happening with JQM 1.2, you should carefully document it and file an Issue on Github, once you are sure it is not due to something you are doing. (Which is impossible for us to help you with based on just a picture.)
If you are using an older version of JQM, be advised that the JQM developers are not mind-readers, and older versions were released prior to the release of iPhone 5.
Posting something more than a picture would be helpful.