diff --git a/core/attributedef.class.inc.php b/core/attributedef.class.inc.php
index 0a5af24a8..799623557 100644
--- a/core/attributedef.class.inc.php
+++ b/core/attributedef.class.inc.php
@@ -6529,37 +6529,46 @@ class AttributeDateTime extends AttributeDBField
 		}
 	}
 
-    /**
-     * @inheritDoc
-     *
-     * @param int|string $proposedValue timestamp ({@see DateTime::getTimestamp()) or date as string, following the {@see GetInternalFormat} format.
-     */
+	/**
+	 * @inheritDoc
+	 *
+	 * @param int|DateTime|string $proposedValue possible values :
+	 *                      - timestamp ({@see DateTime::getTimestamp())
+	 *                      - {@see \DateTime} PHP object
+	 *                      - string, following the {@see GetInternalFormat} format.
+	 *
+	 * @throws \CoreUnexpectedValue if invalid value type or the string passed cannot be converted
+	 */
 	public function MakeRealValue($proposedValue, $oHostObj)
 	{
 		if (is_null($proposedValue))
 		{
 			return null;
 		}
-		if (is_string($proposedValue) && ($proposedValue == "") && $this->IsNullAllowed())
-		{
-			return null;
+
+		if (is_numeric($proposedValue)) {
+			return date(static::GetInternalFormat(), $proposedValue);
 		}
-		if (!is_numeric($proposedValue))
-		{
-			// Check the format
-			try
-			{
-				$oFormat = new DateTimeFormat($this->GetInternalFormat());
+
+		if (is_object($proposedValue) && ($proposedValue instanceof DateTime)) {
+			return $proposedValue->format(static::GetInternalFormat());
+		}
+
+		if (is_string($proposedValue)) {
+			if (($proposedValue === '') && $this->IsNullAllowed()) {
+				return null;
+			}
+			try {
+				$oFormat = new DateTimeFormat(static::GetInternalFormat());
 				$oFormat->Parse($proposedValue);
-			} catch (Exception $e)
-			{
-				throw new Exception('Wrong format for date attribute '.$this->GetCode().', expecting "'.$this->GetInternalFormat().'" and got "'.$proposedValue.'"');
+			} catch (Exception $e) {
+				throw new CoreUnexpectedValue('Wrong format for date attribute '.$this->GetCode().', expecting "'.$this->GetInternalFormat().'" and got "'.$proposedValue.'"');
 			}
 
 			return $proposedValue;
 		}
 
-		return date(static::GetInternalFormat(), $proposedValue);
+		throw new CoreUnexpectedValue('Wrong format for date attribute '.$this->GetCode());
 	}
 
 	public function ScalarToSQL($value)
diff --git a/core/dbobject.class.php b/core/dbobject.class.php
index 7a850dba1..757508dc2 100644
--- a/core/dbobject.class.php
+++ b/core/dbobject.class.php
@@ -4745,7 +4745,7 @@ abstract class DBObject implements iDisplay
 			}
 		}
 		$oDate->modify($sModifier);
-		$this->Set($sAttCode, $oDate->getTimestamp());
+		$this->Set($sAttCode, $oDate);
 	}
 
 	/**
diff --git a/tests/php-unit-tests/unitary-tests/core/DBObjectTest.php b/tests/php-unit-tests/unitary-tests/core/DBObjectTest.php
index 94111d6eb..2c5eaa0d8 100644
--- a/tests/php-unit-tests/unitary-tests/core/DBObjectTest.php
+++ b/tests/php-unit-tests/unitary-tests/core/DBObjectTest.php
@@ -20,9 +20,11 @@
 namespace Combodo\iTop\Test\UnitTest\Core;
 
 use Attachment;
+use AttributeDateTime;
 use Combodo\iTop\Service\Events\EventData;
 use Combodo\iTop\Test\UnitTest\ItopDataTestCase;
 use CoreException;
+use DateTime;
 use DBObject;
 use InvalidExternalKeyValueException;
 use lnkContactToFunctionalCI;
@@ -412,7 +414,55 @@ class DBObjectTest extends ItopDataTestCase
 		$oObject->Set('org_id', 3);
 		$this->assertDBQueryCount(1, function() use (&$oObject){
 			static::assertNotEmpty($oObject->Get('org_name'));
-		});	}
+		});
+	}
+
+	/**
+	 * @covers AttributeDateTime::MakeRealValue
+	 */
+	public function testSetAttributeDateTimeWithTimestamp(): void
+	{
+		$oUserRequest = $this->CreateUserRequest(0);
+		$iNow = time();
+		$oMyDate = new DateTime('2024-02-14 18:12');
+		$sMyDate = $oMyDate->format(AttributeDateTime::GetInternalFormat());
+
+		// First test string obtained with Get() converts into a standard DateTime object
+		$oUserRequest->Set('start_date', $iNow);
+		$sSavedDate = $oUserRequest->Get('start_date');
+		$oSavedDate = new DateTime($sSavedDate);
+		$this->assertSame($iNow, $oSavedDate->getTimestamp());
+
+		// Second test that string obtained with Get() is of the \AttributeDateTime::GetInternalFormat format
+		$oUserRequest->Set('start_date', $oMyDate->getTimestamp());
+		$this->assertEquals($sMyDate, $oUserRequest->Get('start_date'));
+	}
+
+	/**
+	 * @covers AttributeDateTime::MakeRealValue
+	 */
+	public function testSetAttributeDateTimeWithString(): void
+	{
+		$oUserRequest = $this->CreateUserRequest(0);
+		$oMyDate = new DateTime('2024-02-14 18:12');
+		$sMyDate = $oMyDate->format(AttributeDateTime::GetInternalFormat());
+
+		$oUserRequest->Set('start_date', $sMyDate);
+		$this->assertEquals($sMyDate, $oUserRequest->Get('start_date'));
+	}
+
+	/**
+	 * @covers AttributeDateTime::MakeRealValue
+	 */
+	public function testSetAttributeDateTimeWithDateTime(): void
+	{
+		$oUserRequest = $this->CreateUserRequest(0);
+		$oMyDate = new DateTime('2024-02-14 18:12');
+		$sMyDate = $oMyDate->format(AttributeDateTime::GetInternalFormat());
+
+		$oUserRequest->Set('start_date', $oMyDate);
+		$this->assertEquals($sMyDate, $oUserRequest->Get('start_date'));
+	}
 
 	/**
 	 * @group Integration
diff --git a/tests/php-unit-tests/unitary-tests/webservices/ImportTest.php b/tests/php-unit-tests/unitary-tests/webservices/ImportTest.php
index 08663eed3..725f7ead0 100644
--- a/tests/php-unit-tests/unitary-tests/webservices/ImportTest.php
+++ b/tests/php-unit-tests/unitary-tests/webservices/ImportTest.php
@@ -127,7 +127,7 @@ class ImportTest extends ItopDataTestCase {
 			'"first_name","name", "email", "org_id->name", obsolescence_date',
 			sprintf('"%s", "%s", "%s", UID, toto', $sFirstName, $sLastName, $sEmail),
 			sprintf(
-				'Issue: Internal error: Exception, Wrong format for date attribute obsolescence_date, expecting "Y-m-d" and got "toto";n/a;n/a;n/a;%s;%s;%s;toto', $sFirstName, $sLastName, $sEmail
+				'Issue: Internal error: CoreUnexpectedValue, Wrong format for date attribute obsolescence_date, expecting "Y-m-d" and got "toto";n/a;n/a;n/a;%s;%s;%s;toto', $sFirstName, $sLastName, $sEmail
 			),
 			null,
 			1,
@@ -174,7 +174,7 @@ CSVFILE;
 		foreach (["ORGID" => $iOrgId, "UID" => $this->sUid] as $sSearch => $sReplace){
 			$sLastLineNeedle = str_replace($sSearch, $sReplace, $sLastLineNeedle);
 		}
-		$this->assertStringContainsString($sLastLineNeedle, $sLastline, $sLastline);
+		$this->assertStringContainsString($sLastLineNeedle, $sLastline, 'The script we launched in an external process returned a value different than the expected error message');
 
 		$sPattern = "/Person;(\d+);/";
 		if (preg_match($sPattern,$sLastline,$aMatches)){