D3DXSaveSurfaceToFile() is nowhere to be found.

[pacemkr]

This is really starting to piss me off. Someone please prove me wrong.

Here is a link to the function in DX 9 sdk.
msdn (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/directx9_c/directx/graphics/reference/d3dx/functions/texture/d3dxsavesurfacetofile.asp)

Following dll's are referenced in my program.
Microsoft.DirectX.dll
Microsoft.DirectX.Direct3D.dll
Microsoft.DirectX.Direct3DX.dll

The code:

using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;
.
.
//here trying to call D3DXSaveSurfaceToFile
//the parameters are wrong but thats not the problem
D3DXSaveSurfaceToFile();

The eror I get: "The name does not exist in MainFrom..." bla bla

In other words, I cannot locate the function. Where is it?
Please help.

If it helps, here is the link to what I am trying to do. The only problem the link is in C++.
codeproject (http://www.codeproject.com/dialog/screencap.asp#And%20The%20DirectX%20way%20of%20doing%20it%20:)

Thanks in advance.