Have you installed
MacTex? Seems like they do a set of changes to a bunch of resource files that the others are referring to.
How to fix it? Try doing below commands in the terminal to find which file might be affected
grep setloginpath /etc/*
grep setloginpath ~/.*
First line is to check the system wide configuration files for
setloginpath and the second line to check your user account configuration files for
Hopefully you will find a file containing something in the line with
setloginpath added /usr/local/bin start at Sun Dec 20 01:00:21 PST 2009
When you found it you will have to remove the problematic line...