Hello, i have tried menuet64 on a netbook with atom cpu menuet says that long mode is not available. Is a bug or really the atom do not supports long mode?
i tried the floppy disk version on a usb pendrive.

Atom doesn't support long mode. I was disappointed to see CPUID results, I would have liked programming in 64bit mode

Please, do not generalize:
http://ark.intel.com/Product.aspx?id=35635 - 64-bit
http://ark.intel.com/Product.aspx?id=35641 - 64-bit
(other three represented in ark don't support 64-bit, though)

me too,i'm surprised that many years after the first x86 64bit cpu was made still 32 bit cpu are made,and 32bit windows is common.
And thanks to intel for their confusing marketing.

OK, only some Atoms don't support long mode. Since 64-bit mode must be implemented together with 32-bit mode, it requires adding a lot of transistors: to keep power consumption low, it can make sense cutting long mode away.
Of course it's impossible to market a processor without 32-bit mode: we know that in IT everything is spread and established will stay nearly forever, however bad it is. In fact, x86 instruction set is considered by many programmers - including me - one of the worst around, and even Intel couldn't introduce something new: see Itanium story...