I'm with Steven!
1) Re-install your server completely.
2) Make a back up of your configuration files (To me, this is Rule #1 when fiddling with anything that you need root permissions for. Root permissions are there for a reason ...)
3) Change your config files incrementally and carefully investigate the results of your changes.
4) Use the backed up versions to make everything OK again!
Remember - make back ups! Make back ups! Make back ups!!!! You'll save yourself a very big headache if you do!!!!