Yes, they do have EMH's during October. We took advantage of them while at WDW on our October, 2003 trip.
I would assume they will have both the EMH's and new evening equivalent (extended evening hours on certain nights, for those staying on site) during October of 2005. They just don't have those schedules posted this far in advance. Check the WDW calendars around June or July, as the October park hours and EMH info should be made available to the public by around then. They usually try to have that info online in plenty of time for people to make decisions and schedule their PS ressies. Be aware, however, that like many things the EMH's (& park hours in general) can be subject to change without much advance notice.
We happened to be at AK on Columbus day of 2003, and found out from a CM that Disney had decided to extend that park's hours for the day (because of the holiday crowds)--instead of closing at 5 PM, as previously advertised, they were remaining opened until 7 PM. We had PS at Rainforest Cafe, and decided to go back into the park after we ate. As we were walking back in towards the TOL, the masses were all departing for the day! We had the park practically to ourselves that evening, and there were no wait lines for anything. I think at least 95% + of the visitors never even knew, and believed that the park had indeed been closing at 5 PM.
Moral of the story...
Check the schedules regarding park hours and EMH's when planning your trip in advance. Then double check again upon arrival at WDW for any updates or changes to the schedule. And don't be shy about talking with the CM's at the various parks--you never know what sort of good info they may have for you that may make your visit to the World that much more magical!