I have three ActiveX controls I have written using MFC and C++. When I use the depedency walker on PPSQL.EXE, only four DLLS are shown as being called directly

MSVCR70.DLL
KERNEL32.DLL
USER32.DLL
ADVAPI32.DLL

I have searched my VFP source for calls to UnregisterDeviceNotification. There are none.

How can I determine where UnregisterDeviceNotification is called from, assuming it is called somehow. It seems like I remember some tool that would produce a text output of the calling chain that could be searched for the function name, but I'm not having any luck finding it.