The link previously posted says it's outdated, but I found Annie's recipe:
"Wallpaper Paste by Annie Berthold-Bond, Care2.com Producer, Green Living Channels
People ask me for this old folk recipe all the time. Everybody claims that there is no commercial wallpaper paste that works as well and is free of pesticides!
Simple Solution: 1 cup flour (wheat, corn, or rice) 3 teaspoons alum water 10 drops oil of cloves (natural preservative)
Combine the flour and alum in a double boiler. (If you don't have a double boiler, set a smaller pan inside a bigger one that contains enough water that can be brought to a boil without overflowing). Add enough water to make a consistency of heavy cream; stir until blended. Heat, stirring constantly, until the mixture has thickened to a gravy texture. Let cool. Stir in the clove oil. Pour into a glass jar with a screw top. Apply with a glue brush. Makes 1 cup Shelf Life: 2 weeks refrigerated
Helpful Hints: Alum is available in the herb section of most supermarkets. 20 Mule Team Borax (found in laundry section of grocery stores) can be used as an alternative to alum. Clove oil is found in pharmacies and health food stores."