http://bugs.winehq.org/show_bug.cgi?id=33993
--- Comment #3 from Dan Kegel dank@kegel.com 2013-07-09 09:42:58 CDT --- Scratch that. 'winetricks jet40' simply doesn't handle 64 bit systems properly. ( https://code.google.com/p/winetricks/issues/detail?id=327 )
Ian, does the app actually fail to install, or are you just scared off by those failure messages? It's quite possible that jet installed ok despite those warnings.
If the app is actually unhappy, does export WINEARCH=win32 before creating the wineprefix help?