Where is the kernel configuration stored?

I currently run Angstrom Linux 2.6.32. I intend to upgrade the Linux kernel from 2.6.32 to 3.0.7. For this reason, I had to configure kernel 3.0.7 by running make menuconfig.

Now, I want to compare the new kernel configuration with the previous, but I can’t find the kernel 3.0.7 configuration file. Any ideas?