diff --git a/src/toruschess.cpp b/src/toruschess.cpp
index 75fac17..9f1beb4 100644
--- a/src/toruschess.cpp
+++ b/src/toruschess.cpp
@@ -84,11 +84,11 @@ namespace toruschess {
 		return Pos(p.x() + d.x, p.y() + d.y);
 	}
 
-	QList<Move> Field::validMoves(const Pos &from) const {
+	QList<Move> Field::simpleValidMoves(const Pos &from) const {
 		QList<Move> moves;
 		int thePlace = place(from);
 		Piece thePiece = (Piece) qAbs(thePlace);
-		qDebug("validMoves: %i", thePiece);
+// 		qDebug("simpleValidMoves: %i", thePiece);
 		switch (thePiece) {
 		case NOPIECE:
 			break;
@@ -131,10 +131,42 @@ namespace toruschess {
 			}
 			break;
 		}
-		qDebug("validMoves: found %i", moves.size());
+// 		qDebug("simpleValidMoves: found %i", moves.size());
 		return moves;
 	}
 	
+	QList<Move> Field::validMoves(const Pos &from) const {
+		QList<Move> moves = simpleValidMoves(from);
+		int thePlace = place(from);
+		Pos pking(0,0);
+		/* find king */
+		for (int x = 0; x < 8; x++) for (int y = 0; y < 8; y++) {
+			if (piece(Pos(x, y)) == KING && 0 < place(Pos(x, y)) * thePlace) {
+				pking = Pos(x, y);
+				goto foundking;
+			}
+		}
+		return QList<Move>(); /* error, no king found */
+foundking:
+		QList<Move> resMoves;
+		Field testField(*this);
+		testField.place(from) = 0;
+		bool movedKing = (from == pking);
+		foreach(Move m, moves) {
+			testField.place(m.to()) = thePlace;
+			for (int x = 0; x < 8; x++) for (int y = 0; y < 8; y++) {
+				Pos curp(x, y);
+				if (0 > testField.place(curp) * thePlace && testField.simpleValidMoves(curp).contains(Move(&testField, curp, movedKing ? m.to() : pking))) {
+					goto invalidmove;
+				}
+			}
+			resMoves.push_back(m);
+invalidmove:
+			testField.place(m.to()) = m.prevTo();
+		}
+		return resMoves;
+	}
+	
 	bool Field::validMove(const Move &m) const {
 		QList<Move> moves = validMoves(m.from());
 		return moves.contains(m);
diff --git a/src/toruschess.h b/src/toruschess.h
index 38e63a4..a7d7ece 100644
--- a/src/toruschess.h
+++ b/src/toruschess.h
@@ -42,7 +42,7 @@ namespace toruschess {
 		int x() const { return m_x; }
 		int y() const { return m_y; }
 		
-		bool operator==(const Pos &other) {
+		bool operator==(const Pos &other) const {
 			return m_x == other.m_x && m_y == other.m_y;
 		}
 		
@@ -60,7 +60,7 @@ namespace toruschess {
 		int prevTo() const { return m_prevTo; }
 		Player player() const { return m_player; }
 		
-		bool operator==(const Move &other) {
+		bool operator==(const Move &other) const {
 			return m_from == other.m_from
 			    && m_to == other.m_to
 			    && m_prevFrom == other.m_prevFrom
@@ -92,6 +92,8 @@ namespace toruschess {
 		bool undo(const Move &m);
 		
 	private:
+		QList<Move> simpleValidMoves(const Pos &from) const;
+	
 		int m_places[8][8];
 	};
 
diff --git a/toruschess.kdevelop b/toruschess.kdevelop
index e2f6c5e..800e167 100644
--- a/toruschess.kdevelop
+++ b/toruschess.kdevelop
@@ -152,13 +152,13 @@
       <autokdesu>false</autokdesu>
       <envvars/>
       <runarguments>
-        <toruschess></toruschess>
+        <toruschess/>
       </runarguments>
       <cwd>
         <toruschess>/home/stefan/studium/7. semester/fapra_vis/src/toruschess/..</toruschess>
       </cwd>
       <debugarguments>
-        <toruschess></toruschess>
+        <toruschess/>
       </debugarguments>
     </run>
     <general>