id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
26449	formfield_overrides doesn't work for models.DateTimeField with SplitDateTimeWidget	Marysia Lowas-Rzechonek	nobody	"When you override the default widget used in Django Admin for models.DateTimeField using formfield_overrides with any widget that derives from SplitDateTimeWidget, the form will not pass the validation with 'Enter a valid date/time.' error message.

It seems that when updating the default formfield_overrides dict, it overrides the default values instead of merging them. At present, it seems to affect only the DateTimeField.

So, this code will trigger the error: 'Enter a valid date/time.'
    formfield_overrides = {models.DateTimeField: {widgets.AdminSplitDateTime},}

And this code will be fine:
    formfield_overrides = {models.DateTimeField: {'form_class': forms.SplitDateTimeField,'widget': widgets.AdminSplitDateTime},}

The problem in django/contrib/admin/option.py around line 117."	Uncategorized	new	contrib.admin	1.9	Normal				Unreviewed	0	0	0	0	0	0