A little problem with a demon

[Franco castro]

Hi guys, I have a some servers running linux, also I have instelled on them
"deny hosts" wich is a tool to prevent brute force atacks, but it stop
working 3 or 4 times per month, when I saw my statics is obviosly knowed
that deny hosts have stop working, I can see around 8k invalid user login
atempts, I'm thinking in ad a crontab line to delete the file lock, and
start denyhosts every 6 hours, but it's probably not the best choice, may be
anyone of you know some kind of program how make sure the program still
runing or something like that, tnks :D