diff --git a/search2/search/fields/CheckedOutDeltaField.inc.php b/search2/search/fields/CheckedOutDeltaField.inc.php
index ad4721a..798093c 100644
--- a/search2/search/fields/CheckedOutDeltaField.inc.php
+++ b/search2/search/fields/CheckedOutDeltaField.inc.php
@@ -23,8 +23,7 @@ class CheckedOutDeltaField extends DBFieldExpr
 
     public function modifyValue($value)
     {
-
-    	return "cast($this->modifiedName + $value as date)";
+    	return "cast(cast($this->modifiedName as date) + $value as date)";
     }
 
     public function getInputRequirements()
diff --git a/search2/search/fields/CreatedDeltaField.inc.php b/search2/search/fields/CreatedDeltaField.inc.php
index fa87990..0a3e1d6 100755
--- a/search2/search/fields/CreatedDeltaField.inc.php
+++ b/search2/search/fields/CreatedDeltaField.inc.php
@@ -23,8 +23,7 @@ class CreatedDeltaField extends DBFieldExpr
 
     public function modifyValue($value)
     {
-
-    	return "cast($this->modifiedName + $value as date)";
+		return "cast(cast($this->modifiedName as date) + $value as date)";
     }
 
     public function getInputRequirements()
diff --git a/search2/search/fields/ModifiedDeltaField.inc.php b/search2/search/fields/ModifiedDeltaField.inc.php
index 55927a8..9a5a2f6 100755
--- a/search2/search/fields/ModifiedDeltaField.inc.php
+++ b/search2/search/fields/ModifiedDeltaField.inc.php
@@ -22,7 +22,7 @@ class ModifiedDeltaField extends DBFieldExpr
 
     public function modifyValue($value)
     {
-    	return "cast($this->modifiedName + $value as date)";
+		return "cast(cast($this->modifiedName as date) + $value as date)";
     }
 
     public function getInputRequirements()