so i've thought by myself how awesome i'd be if i could reset the whole world. the whole game. and start all over again with my full equipped high level char. just for fun.
i deleted every *.map, *.ent and *.opq i found in my folder and started my game - and guess what? it worked!
everything was back again. every fanged salamander, every npc, every chest and barrel intact and closed.
the only problem was ... it didn't reset the quests. so i wouldn't exactly play the game again since i couldn't do the quests. i just could slaughter through all those mobs again, explore all the dungeons again and put some color on my empty mini map.
so i played around a bit and found out that your journal/questlog is located in your character file. you can delete it easily with any hex-editor you want.
To reset the world of Eschalon to explore it once more:
just start a new game with a dummy character, save it, delete the char-file in your savegame folder and replace it with a copy of your real character.
open the file with a hex editor and delete your questlog.

load.
enjoy!