using the heap debugger

[kufdam]

I am trying to trap some memory leaks using the debug heap functions.
The following statements set up the heap debugger.

#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>

However, when I use _CrtDumpMemoryLeaks();

I get information in the following format (ONLY ONE EXAMPLE SHOWN BELOW, ALL ARE IN IDENTICAL FORMAT):

 c:\program files\microsoft visual studio\vc98\include\crtdbg.h(552) : {31} normal block at 0x00684260, 1024 bytes long.
 Data: <                > 07 00 00 00 08 00 00 00 CC CC CC CC 06 00 00 00

The line numbers are supposed to refer to the line in any of my source files where leaking memory is allocated, but the line numbers displayed refer to the heap debugger header file!

Does anybody have any idea what is going on here? Why are the line numbers referring to the heap debugger header file?

Any help much appreaciated.