I am using the following configuration:
1) Qt SDK 1.1.3 - Qt 4.7.4.
2) Intel Composer XE 2011 - Intel C/C++ compiler 12.0.5/
3) Windows 7 Ultimate 64-bit

I have successfully compiled Qt 4.7.4 using the 64-bit version of the Intel compiler but I cannot add a tool chain that specifies the Intel compiler.

I have noticed that all Microsoft compilers are automatically detected through a .bat initialization file. Such file is available for the Intel compiler as well, but it is not detected automatically. The PATH system variable contains all needed Intel compiler paths.

A bug will submitted that targets the win32-icc make specification or the "QtSDK/QtSources/4.7.4" folder contents - the Qt 4.7.4 SDK itself. The specification needs the "examples" and "demos" folder to be available in the "QtSDK/QtSources/4.7.4/" folder. The folders "Examples" and "Demos" (note that they begin with uppercase letter here) are situated in the "QtSDK" folder.
The solution:
1) copy the "QtSDK/QtSources/4.7.4" folder in "QtSDK/Desktop/Qt/4.7.4" and rename it, let's say, "icc-xx" where "xx" stands for 32 or 64-bit build. So, in my case the folder is - "QtSDK/Desktop/Qt/4.7.4/icc-64".
2) copy the "QtSDK/Demos" and "QtSDK/Examples" folders in "QtSDK/Desktop/Qt/4.7.4/icc-xx".
3) Rename "Demos" to "demos" and "Examples" to "examples".
4) Go in the "demos/4.7" folder and move its contents to "demos" folder.
5) Do the same for "examples" folder. Leave "examples/notifications" in place.
6) Open either "IA-32 Visual Studio 2010/2008/2005 mode" or "Intel 64 Visual Studio 2010/2008/2005 mode" Intel command-prompt.
7) Navigate to "QtSDK/Desktop/Qt/4.7.4/icc-xx" using the already started command-prompt.
8) Type: "configure -platform win32-icc".
9) After the configuration tool has done its work, type "nmake" and wait for several hours.
10) Open Qt Creator (note that Qt Creator is not build as part of the Qt 4.7.4 SDK).
11) Go to "Tools/Options" and choose "Qt4" in the left pane of the dialog that is shown.
12) All built Qt versions - automatically detected and manually found such, are mentioned on the right side.
13) Click on the "Add" button and navigate to "QtSDK/Desktop/Qt/4.7.4/icc-xx/bin/qmake.exe". Name this custom Qt version "Qt 4.7.4 for Desktop - icc" for example.
14) Create an empty GUI Widget project and choose this custom Qt version, built with Intel's compiler, to build your project.
15) Start the build and see the "Compile Output" window - it states that qmake uses "win32-msvc2010/2008/2005" make specification when building your project.
That is true - look in the "Projects" section situated on the left sidebar and give a note of the toolchain being used.
16) Now it is the time to create a new toolchain that specifies the Intel C/C++ compiler.

17) Go to "Tools/Options" and click on "Tool Chains" in the left side of the dialog that has popped up.
18) Notice that there is no automatically added toolchain for the Intel compiler.
19) I have added a new MinGW toolchain, set the compiler path to: "C:\Program Files (x86)\Intel\ComposerXE-2011\bin\intel64\icl.exe".
20) I set the ABI to: <custom> x86 windows msys pe 64-bit.
21) I set the debugger to: "C:\Program Files (x86)\Intel\ComposerXE-2011\debugger\intel64\DebugExtensionServer64.exe" - probably it is not the real debugger’s executable.
22) Now after the tool chain has been added, go again to the “Qt4” section and select the newly added Qt version built with the Intel compiler.
23) In the bottom-right corner of the current window – just above the “Apply” button, there is a “Details” button. Click on it to show the used and available tool chains. The newly created Intel compiler tool chain is not available in the list of Qt versions.
24) Go back to the list of available “Tool Chains” and select an arbitrary tool chain that uses MSVC. Note in the bottom of the window that instead of having the executable of the compiler and debugger, a .bat file is mentioned - vcvarsall.bat, which contains all compiler, debugger, linker directories, settings, etc. The same file exists for the Intel compiler, but I failed to provide it through the Qt Creator interface, since all of the tool chains that are specified by a .bat file name are automatically added.
The article mentions that only the Linux version of the Intel compiler gets automatically detected.
25) QtSDK\QtCreator\share\qtcreator\Nokia\toolchains.x ml contains some descriptions of tool chains but no .bat files are specified there.
How to add a Intel compiler tool chain?