"Support for shared 32/64-bit setups" ?

[StringCheesian]

Does that mean a single prefix for both 32 bit and 64 bit apps?
Does it mean a single installation of wine for the same?

Well, however it works it's a good idea. I think a lot of 64 bit Windows apps right now are actually 32/64 hybrids that do install some 32 bit stuff too. Especially suites of multiple apps.

Tonglebeak of the Gentoo forums asked the same question: http://forums.gentoo.org/viewtopic.php?p=6229606
I just thought we're more likely to get an answer here.

[hellork]

Does that mean a single prefix for both 32 bit and 64 bit apps?
Does it mean a single installation of wine for the same?

Well, however it works it's a good idea. I think a lot of 64 bit Windows apps right now are actually 32/64 hybrids that do install some 32 bit stuff too. Especially suites of multiple apps.

Tonglebeak of the Gentoo forums asked the same question: http://forums.gentoo.org/viewtopic.php?p=6229606
I just thought we're more likely to get an answer here.

In the shortlog for wine-1.1.42 in the announcement http://www.winehq.org/announce/1.1.42 there are a lot of references to WOW64, which tells me they're working on it. What the status is I don't know. Try it!

[Thunderbird]

Let me give a short explanation. A 64-bit Wine needs to work together with 32-bit Wine because a lot of 64-bit apps for instance ship with 32-bit installers. The way we handle mixing 32-bit/64-bit is done the same way as in Windows. For files this means that all 64-bit stuff is in places like c:\Program Files and c:\windows\system32 (yes, system32 for 64-bit). 32-bit stuff is in c:\Program Files(x86) and c:\windows\syswow64 (yes, this is where 32-bit stuff is). A 32-bit windows program isn't aware that it is stored in the x86 Program Files, since that is handled under the hood (wineserver is taking care of it). Similar magic is performed inside the registry, so you have 'normal' and also wow64 keys for 32-bit stuff.

A 32-bit/64-bit Wine requires duplicates of all wine libraries and binaries (except for wineserver which is shared and is a 64-bit app).

Another warning if you are currently using a 32-bit Wine and you want to move to the 64-bit version, your old wine prefix won't work (remember, it lacks the wow64 magic). This is a transition problem.

[MalleRIM]

All this suggests, that it does work. But I can't find anything about how it's done. I'd like some explanations on that.

[Thunderbird]

Not sure what you want to know but some details are here:
http://wiki.winehq.org/Wine64
http://wiki.winehq.org/Wine64ForPackagers

Note while the architecture is now in place only a few basic 64-bit apps work. It will take a long time before more complicated apps work.