Reuses a dictionnary for the hash table to reduce the string compare
costs. Not worth it unless validating big DTDs

		without		with
db10000  tree	175/79		179/81
db100000 stream	1222		1217
dba100000stream	593		601
REC validation	1986		2098
Docbook valid	10808		10649

Tue Feb 24 19:09:49 CET 2004
