I'm not sure you can expect a 32-bit operating system like Windows 2000 to offer access to 64-bit memory and data features seamlessly if it is running in 32-bit emulation.
In the end, the operating system has to use the new IA-64 to get those features, and if the standard OS is compiled to IA-32, then of course you will need a special version of the OS, compiled to IA-64.
Of course, properly implemented, an operating system could bridge this emulation issue internally, as Apple's Macintosh OS does across the 680x0 and PowerPC instruction sets. However, the structural changes required to Windows 2000 might have created far too much complexity to be feasible in the product cycle.
After all, if you are going to buy an Itanium box, you are not going to blink at needing a special version of Windows 2000 for it. Just because you need a special version of the OS does not imply you will need special versions of any 32-bit applications... unless, of course, you want them to provide access to 64-bit features.
It is possible that Microsoft has provided migratory APIs that offer 64-bit features, but in a manner that is compatible with execution on 32-bit processors. Anyone care to substantiate this conjecture? |
