diff --git a/application/core/DB_Model.php b/application/core/DB_Model.php
index e0cd6631c..f1bf03407 100644
--- a/application/core/DB_Model.php
+++ b/application/core/DB_Model.php
@@ -137,9 +137,11 @@ class DB_Model extends FHC_Model
 			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
 		
 		
-		// Check rights
-		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
-			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
+		// Check rights only if this method is called from a model
+		//var_dump(get_called_class());
+		if (substr(get_called_class(), -6) == '_model')
+			if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
+				return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
 
 		// DB-SELECT
 		// Check for composite Primary Key
@@ -173,8 +175,11 @@ class DB_Model extends FHC_Model
 			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
 		
 		// Check rights
-		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
-			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
+		// Check rights only if this method is called from a model
+		//var_dump(get_called_class());
+		if (substr(get_called_class(), -6) == '_model')
+			if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 's'))
+				return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
 
 		// DB-SELECT
 		if (is_null($where))
@@ -199,8 +204,11 @@ class DB_Model extends FHC_Model
 			return $this->_error(lang('fhc_'.FHC_NODBTABLE), FHC_MODEL_ERROR);
 		
 		// Check rights for joined table
-		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$joinTable], 's'))
-			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$joinTable], FHC_MODEL_ERROR);
+		// Check rights only if this method is called from a model
+		//var_dump(get_called_class());
+		if (substr(get_called_class(), -6) == '_model')
+			if (! $this->fhc_db_acl->isBerechtigt($this->acl[$joinTable], 's'))
+			 return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$joinTable], FHC_MODEL_ERROR);
 
 		$this->db->join($joinTable, $cond, $type);
 		
@@ -270,9 +278,11 @@ class DB_Model extends FHC_Model
 		if (is_null($this->pk))
 			return $this->_error(lang('fhc_'.FHC_NOPK), FHC_MODEL_ERROR);
 		
-		// Check rights
-		if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'd'))
-			return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
+		// Check rights only if this method is called from a model
+		//var_dump(get_called_class());
+		if (substr(get_called_class(), -6) == '_model')
+			if (! $this->fhc_db_acl->isBerechtigt($this->acl[$this->dbTable], 'd'))
+				return $this->_error(lang('fhc_'.FHC_NORIGHT).' -> '.$this->acl[$this->dbTable], FHC_MODEL_ERROR);
 
 		// DB-DELETE
 		// Check for composite Primary Key
diff --git a/include/benutzer.class.php b/include/benutzer.class.php
index 7bbc740a6..105639175 100644
--- a/include/benutzer.class.php
+++ b/include/benutzer.class.php
@@ -51,6 +51,12 @@ class benutzer extends person
 	 */
 	public function load($uid = null)
 	{
+		if (empty($uid))
+		{
+			$this->errormsg = "UID not set!";
+			return false;
+		}
+
 		$qry = "SELECT * FROM public.tbl_benutzer WHERE uid=".$this->db_add_param($uid);
 
 		if($this->db_query($qry))
diff --git a/include/berechtigung.class.php b/include/berechtigung.class.php
index 50a1c05e3..ac140eead 100644
--- a/include/berechtigung.class.php
+++ b/include/berechtigung.class.php
@@ -52,6 +52,12 @@ class berechtigung extends Berechtigung_model
 	 */
 	public function load($berechtigung_kurzbz = null)
 	{
+		if (empty($berechtigung_kurzbz))
+		{
+			$this->errormsg = "berechtigung not set!";
+			return false;
+		}
+
 		$result = parent::load($berechtigung_kurzbz);
 		
 		if (is_object($result) && $result->error == EXIT_SUCCESS && is_array($result->retval))
diff --git a/include/funktion.class.php b/include/funktion.class.php
index faf3daeee..6e72a9631 100644
--- a/include/funktion.class.php
+++ b/include/funktion.class.php
@@ -111,7 +111,8 @@ class funktion extends Funktion_model
 	 */
 	public function load($funktion_kurzbz = null)
 	{
-		if ($funktion_kurzbz == '')
+		
+		if (empty($funktion_kurzbz) || $funktion_kurzbz == '')
 		{
 			$this->errormsg = 'funktion_bz darf nicht leer sein';
 			return false;
@@ -218,4 +219,4 @@ class funktion extends Funktion_model
 		}
 	}
 }
-?>
\ No newline at end of file
+?>
diff --git a/include/studiensemester.class.php b/include/studiensemester.class.php
index 1ed0b8a1c..13e199655 100644
--- a/include/studiensemester.class.php
+++ b/include/studiensemester.class.php
@@ -61,6 +61,12 @@ class studiensemester extends Studiensemester_model
 	 */
 	public function load($studiensemester_kurzbz = null)
 	{
+		if (empty($studiensemester_kurzbz))
+		{
+			$this->errormsg = "studiensemester not set!";
+			return false;
+		}
+
 		$result = parent::load($studiensemester_kurzbz);
 			
 		if (is_object($result) && $result->error == EXIT_SUCCESS && is_array($result->retval))