cuda device code debug cuda device code can not be debugged

i have installed the nvidia toolkit 3.2 and nvidia sdk3.2 on my desktop. i 'm a new beginner, some example programs have been read. i have set the environment parameter on the visual studio 2005, but some trouble is coming ,only debug mode and release mode can be used successfully,on emulation debug ,therefore,the device code (kernel funtion)can not be debugged yet. what should i do ?how to solve it ?your reply should be appreciated .