There seems to be a lot of confusion about WDM and Windows 98 SE. I haven't gone there myself yet because it seems that the Delta drivers seemed to be somewhat buggy for the longest while. Also, M Audio acts as if they have no WDM drivers for Windows 98. I know that the official word is that Windows 98 SE does support WDM. There is also a WDM update for WIndows 98 SE; see
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q242937
They used to post a patch thing there but now they say you have to contact Microsoft Product Support. Here's what they say in the article:
"A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem.
"To resolve this problem, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:
http://support.microsoft.com/directory/overview.asp
"NOTE : In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question."
So it sounds like they are making it a little more difficult than usual to get this.
There's some info about this issue in these threads (at other sites, sorry, Dragon -- but I couldn't find any relevant links here):
http://www.audioforums.com/forums/Forum1/HTML/001543.html
http://www.audioforums.com/forums/Forum21/HTML/000064.html
http://www.musicplayer.com/ubb/ultimatebb.php?ubb=get_topic&f=1&t=002776
It's unclear to me that the WDM drivers listed as "for Win 2000 and XP only" are or would be any different than drivers listed as "for Win 98 SE" or if the vendors are just trying to keep as far away as possible from the hassles involved in getting them to work under that OS.
The bottom line for me is that it appears that WDM drivers
should work in Windows 98 SE but getting there is problematic. Personally, I've decided to wait until I get Windows XP sometime this year, probably, before worrying about it.