diff --git a/content/student/studentDBDML.php b/content/student/studentDBDML.php
index a2c6eca51..290c2e84b 100644
--- a/content/student/studentDBDML.php
+++ b/content/student/studentDBDML.php
@@ -2288,33 +2288,47 @@ if(!$error)
 		}
 		else
 		{
-			foreach ($person_ids as $person_id)
+			$exists = false;
+			if (defined('FAS_DOPPELTE_BUCHUNGSTYPEN_CHECK') && (in_array($_POST['buchungstyp_kurzbz'], unserialize(FAS_DOPPELTE_BUCHUNGSTYPEN_CHECK))))
 			{
-				if($person_id!='')
-				{
-					$buchung = new konto();
-					$buchung->person_id = $person_id;
-					$buchung->studiengang_kz = $_POST['studiengang_kz'];
-					$buchung->studiensemester_kurzbz = $_POST['studiensemester_kurzbz'];
-					$buchung->buchungsnr_verweis='';
-					$buchung->betrag = $_POST['betrag'];
-					$buchung->buchungsdatum = $_POST['buchungsdatum'];
-					$buchung->buchungstext = $_POST['buchungstext'];
-					$buchung->mahnspanne = $_POST['mahnspanne'];
-					$buchung->buchungstyp_kurzbz = $_POST['buchungstyp_kurzbz'];
-					$buchung->credit_points = $_POST["credit_points"];
-					$buchung->insertamum = date('Y-m-d H:i:s');
-					$buchung->insertvon = $user;
-					$buchung->anmerkung = $_POST['anmerkung'];
-					$buchung->new = true;
+				$konto = new konto();
+				$exists = $konto->checkDoppelteBuchung($person_ids, $_POST['studiensemester_kurzbz'], $_POST['buchungstyp_kurzbz']);
+			}
 
-					if($buchung->save())
+			if ($exists)
+			{
+				$errormsg = 'Buchung bereits vorhanden.';
+			}
+			else
+			{
+				foreach ($person_ids as $person_id)
+				{
+					if($person_id!='')
 					{
-						$data = $buchung->buchungsnr;
-					}
-					else
-					{
-						$errormsg .= "Fehler beim Speichern: $buchung->errormsg\n";
+						$buchung = new konto();
+						$buchung->person_id = $person_id;
+						$buchung->studiengang_kz = $_POST['studiengang_kz'];
+						$buchung->studiensemester_kurzbz = $_POST['studiensemester_kurzbz'];
+						$buchung->buchungsnr_verweis='';
+						$buchung->betrag = $_POST['betrag'];
+						$buchung->buchungsdatum = $_POST['buchungsdatum'];
+						$buchung->buchungstext = $_POST['buchungstext'];
+						$buchung->mahnspanne = $_POST['mahnspanne'];
+						$buchung->buchungstyp_kurzbz = $_POST['buchungstyp_kurzbz'];
+						$buchung->credit_points = $_POST["credit_points"];
+						$buchung->insertamum = date('Y-m-d H:i:s');
+						$buchung->insertvon = $user;
+						$buchung->anmerkung = $_POST['anmerkung'];
+						$buchung->new = true;
+
+						if($buchung->save())
+						{
+							$data = $buchung->buchungsnr;
+						}
+						else
+						{
+							$errormsg .= "Fehler beim Speichern: $buchung->errormsg\n";
+						}
 					}
 				}
 			}
diff --git a/include/konto.class.php b/include/konto.class.php
index 09afa5303..6c4891674 100644
--- a/include/konto.class.php
+++ b/include/konto.class.php
@@ -957,6 +957,30 @@ class konto extends basis_db
 			return false;
 		}
 	}
+
+	public function checkDoppelteBuchung($person_ids, $stsem, $typ)
+	{
+		$qry = "SELECT betrag
+				FROM public.tbl_konto
+				JOIN public.tbl_benutzer benutzer USING(person_id)
+				WHERE person_id IN (".$this->implode4SQL(array_filter($person_ids)).")
+				AND studiensemester_kurzbz = ".$this->db_add_param($stsem)."
+				AND buchungstyp_kurzbz = ".$this->db_add_param($typ)." 
+				GROUP BY buchungsnr";
+
+		if ($result = $this->db_query($qry))
+		{
+			if ($this->db_num_rows($result) > 0)
+				return true;
+			else
+				return false;
+		}
+		else
+		{
+			$this->errormsg = 'Fehler bei der Abfrage aufgetreten';
+			return false;
+		}
+	}
 }
 
 ?>