A Vector inside of a Vector

Hi guys, I have a vector of, say, ClassA and in turn ClassA also has another vector of ClassB as its member variable. To instantiate both vectors, I use this routine:

for (int i = 0; i < itemCount; ++i )
	{
		mClassA.increment(); //or ClassB
		ClassA& tempA = mClassA.last(); //or ClassB

		/*The usual initialization for each item of the vector
		*/

		...
	}

The problem is in the second vector / vector of ClassB which is inside of each instance of ClassA, it would crash at this point:

bool VectorResize(U32 *aSize, U32 *aCount, void **arrayPtr, U32 newCount, U32 elemSize)
{
   if (newCount > 0)
   {
      U32 blocks = newCount / VectorBlockSize;
      if (newCount % VectorBlockSize)
         blocks++;
      S32 mem_size = blocks * VectorBlockSize * elemSize;
      *arrayPtr = *arrayPtr ? dRealloc(*arrayPtr,mem_size) :
         [b]dMalloc(mem_size);[/b] //This is where the debugger pointed the crash

      *aCount = newCount;
      *aSize = blocks * VectorBlockSize;
      return true;
   }

   if (*arrayPtr) 
   {
      dFree(*arrayPtr);
      *arrayPtr = 0;
   }

   *aSize = 0;
   *aCount = 0;
   return true;
}

The error message itself is: Unhandled exception at 0x0086b002 in torqueDemo_DEBUG.exe: 0xC0000005: Access violation reading location 0xcdcdcdc8.

How do I solve this? Thanks in advance.

PS: in case anybody asks this, yeah, I've already added the VECTOR_SET_ASSOCIATION keyword.