If you ever encounter two classes named Vector and Group under higher versions of Flex 3.5 from Tour de Flex’s ActionScript Physics Engine, then just rename the files using Flash Builder 4. It has a great way of refactoring in many ways. One of them is renaming files.
Try to create a new project and add a new directory to the Source Path under Flex Build Path properties. Right click the Vector class and rename it anything you like. Let’s say APEVector and APEGroup for the Group class.
When you rename these files, Flash Builder 4 will automatically update the files that are linked to it. It will change all the imports, variable declarations, instantiations, method returns and much more.
Now go and create those motor cycles. Enjoy!