If you are just using the libm log functions, and don't need the rest of ACML, the first note to make is to look at the amdlibm download page and get the most recent amdlibm library.
Here is the link: http://developer.amd.com/libraries/LibM/Pages/default.aspx
The amdlibm math library has one big advantage compared to ACML in that there are no Fortran dependencies which cause link time complications, especially for Windows users. If you only need to use the trancendental functions, then this is highly recommended.
The amdlibm package includes examples, and a build_and_run.bat batch files that illustrates how to use the library with a Visual Studio command prompt.