fix crash
fix crash

svn path=/trunk/KDE/kdeedu/marble/; revision=672342

quannt24/marble,AndreiDuma/marble,tzapzoor/marble,utkuaydin/marble,utkuaydin/marble,tucnak/marble,quannt24/marble,tzapzoor/marble,tzapzoor/marble,David-Gil/marble-dev,probonopd/marble,tucnak/marble,Earthwings/marble,tzapzoor/marble,quannt24/marble,probonopd/marble,AndreiDuma/marble,utkuaydin/marble,quannt24/marble,quannt24/marble,oberluz/marble,Earthwings/marble,tucnak/marble,rku/marble,David-Gil/marble-dev,AndreiDuma/marble,Earthwings/marble,tucnak/marble,AndreiDuma/marble,tzapzoor/marble,adraghici/marble,tucnak/marble,rku/marble,utkuaydin/marble,David-Gil/marble-dev,adraghici/marble,David-Gil/marble-dev,tucnak/marble,utkuaydin/marble,tucnak/marble,adraghici/marble,Earthwings/marble,probonopd/marble,rku/marble,probonopd/marble,AndreiDuma/marble,tzapzoor/marble,oberluz/marble,Earthwings/marble,rku/marble,oberluz/marble,David-Gil/marble-dev,quannt24/marble,oberluz/marble,oberluz/marble,tzapzoor/marble,adraghici/marble,probonopd/marble,quannt24/marble,tzapzoor/marble,Earthwings/marble,adraghici/marble,rku/marble,utkuaydin/marble,AndreiDuma/marble,probonopd/marble,David-Gil/marble-dev,adraghici/marble,oberluz/marble,probonopd/marble,rku/marble