joe, the text I quoted from MSDN was from their download site tree for WindowsXP (subscription access required). Didn't say AMD64, but 64-Bit Extended. This may differ from the Beta CD they released last year. However, didn't say IA-32e - there was no 32 in it at all.
However, the Server version reads:
Windows Server 2003 Prerelease/Beta (Unsupported) . 64-Bit .. 64-Bit Extended Systems (e.g., AMD Opteron, Athlon64) .. Itanium-Based Systems
The client version is identified as:
Windows XP . Windows XP 64-Bit Edition, Version 2003 .. 64-Bit Extended Systems .. Itanium 64-Bit Systems
In the download tree, you download the precise version that interests you. (I don't believe these are put on the standard DVD distribution I get, it is download only.)
However, I agree that IA-32e doesn't seem to be used anywhere. Yesterday I tried the search on the Intel board, wasn't there either. ;)
(Interesting that Itanium is still not supported under Windows 2003.)