Crystal reports with Visual Studio 2012

I'm using crystal reports for creating my reports. I'm using Visual Studio 2012. I use VS2010 to create the reports then I add them to the solution in VS2012. The problem is that I'm getting an exception bobj undefined when I run the report under VS2012. Is is related to the fact that the project is running under VS2012 or is it caused by another thing? Thanks :)