The question was asked at last night's round-table session: What was the command (that is part of CUPS) to convert PPD files for use by Windows clients?

I believe it's part of the work that the "cupsaddsmb" command does, in addition to providing driver files for an appropriately configured Samba server. Check the man page for details.

Note that this may be essentially obsolete these days, as I doubt it properly supports drivers for modern Windows versions, whether they're 32- or 64-bit. However, if you still need it just for the purpose of massaging PPD files (which you would then install, manually or by other means, on the Windows clients), it may still be up to the task.