DPPLAN is a GraphPlan-based planner with a completely different search procedure for solutions. The search is made by a sort of Davis-Putnam principle applied to the nodes of the planning graph. The propagation rules, i.e. the equivalent of simplification rules in propositional logic, are non-directional and can enable the planner to search in backward, forward, bidirectional or even non-directional way.
The graph is built in a compact way using just one level for the facts and one for the action, as in STAN, but using different data structures. In particular nodes and edges have a time label which indicates at what time level they appear/disapper in the planning graph.
DPPLAN is described more in details in the paper presented at AIPS 2000 Conference.
The current version 2.1 (download source files and makefile) is able to solve STRIPS problems (not yet ADL), expressed in PDDL 2.1, with a limited use of numerical resources.
A short manual page can be found here