qmake Makefile does not include a dependency on ui_dialog.h in rule for dialog.o

SETUP:

• Create dialog.ui file in Qt Creator or otherwise
• Run qmake
• Run make
  (by using the Makefile generated by qmake, 'make' correctly generates a ui_dialog.h file from dialog.ui, which is then included in the compiled dialog.o binary)
• Modify dialog.ui
• Rerun make
  (this time, ui_dialog.h is correctly regenerated to reflect the changes in dialog.ui, but the dialog.o binary does not get recompiled)

PROBLEM:

• dialog.o is not regenerated after modifying the dialog user interface file

EFFECT:

• At runtime, dialog UI is not updated to reflect changes - previous original form from dialog.o is used.