error: 'class QLineEdit' has no member named 'setPlaceholderText'
In Qt Creator v. 2.2.0, when a QLineEdit object is added, the generated UI file contains setPlaceholderText. This is a new function (apparently) and creates errors with older versions of Qt.
My "solution" was to simply delete the object since it wasn't necessary for my module. Obviously, a more helpful fix is needed.