The noteworthy changes to be found in today's bi-weekly development snapshot, Wine 1.3.12, include support for multiple icon sizes in the Wine menu builder, improvements to the Wine help browser, initial stab at DOSBox integration, various MSI installer fixes, fixes to the Wine debugger, and various other bug-fixes throughout the Wine stack.
DOSBox is an open-source x86 emulator for DOS that supports a wide variety of DOS applications. DOSBox is compatible with all major operating systems and besides supporting the various flavors of Linux there is also support for even RISC OS, OS/2, BeOS, Solaris 10, and FreeBSD. More information on DOSBox is available at DOSBox.com.
The support for DOSBox in Wine 1.3.12 appears to be limited to trying to execute DOSBox if DOS is not supported natively via the winevdm.
A list of all the Wine 1.3.12 changes can be found at WineHQ.org.