diff --git a/lib/formtastic-separate_html5_date_and_time/active_record.rb b/lib/formtastic-separate_html5_date_and_time/active_record.rb
index 443a10e..d35d44f 100644
--- a/lib/formtastic-separate_html5_date_and_time/active_record.rb
+++ b/lib/formtastic-separate_html5_date_and_time/active_record.rb
@@ -2,10 +2,8 @@ require 'formtastic-separate_html5_date_and_time/processor'
 
 module ActiveRecord
   module ProcessSeparateDateAndTimePickerInputs
-    def assign_multiparameter_attributes(attrs)
-      Formtastic::SeparateDateAndTimePickerInput::Processor.process(attrs).each do |attribute, value|
-        public_send("#{attribute}=", value)
-      end
+    def assign_attributes(attrs = nil, *args)
+      super Formtastic::SeparateDateAndTimePickerInput::Processor.process(attrs), *args
     end
 
     def update_attributes(attrs = nil)
@@ -13,3 +11,4 @@ module ActiveRecord
     end
   end
 end
+
diff --git a/lib/formtastic-separate_html5_date_and_time/processor.rb b/lib/formtastic-separate_html5_date_and_time/processor.rb
index 1a39680..5f3d49b 100644
--- a/lib/formtastic-separate_html5_date_and_time/processor.rb
+++ b/lib/formtastic-separate_html5_date_and_time/processor.rb
@@ -15,7 +15,13 @@ module Formtastic
           end
 
           datetime_attrs.each do |attr, values|
-            attrs[attr] = values["#{attr}(date)"] + ' ' + values["#{attr}(time)"]
+            if !values["#{attr}(date)"].blank?
+              value = (values["#{attr}(date)"] + ' ' + values["#{attr}(time)"]).strip
+
+              if !value.blank?
+                attrs[attr.to_sym] = value
+              end
+            end
 
             attrs.delete("#{attr}(date)")
             attrs.delete("#{attr}(time)")
@@ -27,3 +33,4 @@ module Formtastic
     end
   end
 end
+