Preheat oven to 325°. Cream shortening and sugar together, adding sugar slowly. Beat in eggs, pumpkin and water; set aside. In another bowl, stir together flour, baking powder, salt, cloves, allspice, cinnamon and baking soda. Add to pumpkin mixture and stir well. Stir in nuts. Grease jars well and fill each jar about half full. Place jars on baking sheet and bake for approximately 45 minutes. When done, remove jars, and wipe the sealing edge of the jars. Place lids on jars and close tightly with the ring.
NOTE: Proper sealing of cakes in a jar: After the cake is cooked, be sure to wipe the sealing edge of the jar clean. Place the lids on and close them tightly with the ring. You should hear a "plinking" sound as the jar cools, meaning that they are sealed. You can also press on the lids after the jars have cooled-if they are properly sealed, they should not move at all.
How to serve cake in a jar: Open jar and slide knife around the inside of the jar to loosen the cake and then slide the cake out. Slice and serve alone, with whipped cream or even some ice cream! A 1-pint jar equals approximately 5 slices.
How long they keep: A cake in a jar that has been properly sealed will keep for up to a year.