From: http://www.eskimo.com/~jefffree/recipes/hamafil3.htm

Chop dates. Combine dates, sugar, water and lemon juice in a saucepan.
Stire and cook all the ingrediants until mixture is thick; beat to blend,
or process in food processor until desired consistency. Cool before using
on dough.

Note: for prune filling, substitute 1 lb of prunes for dates.