Newer versions of aspell have been in the tree for a long time, and as far as I can tell no bugs are open for it against AMD64. I have been using aspell 0.60.4 and aspell-en 6.0.0 since February 2006 without experiencing problems. I also use the aspell-nl-0.50.2 package which works fine, so this version of aspell also seems to play nice with older dictionary versions.
Lots of dictionaries are _still_ incompatible, this can't be stabilized until it's solved in some way. *** This bug has been marked as a duplicate of 126109 ***