PATH question

[R Kimber]

"echo $PATH" gives

/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games

"which sensors" gives
/usr/bin/sensors

"ls -l /usr/bin/sensors" gives
-rwxr-xr-x 1 root root 144448 2007-03-07 14:02 /usr/bin/sensors

"sensors" gives
bash: /usr/local/bin/sensors: No such file or directory

What do I need to do to be able to execute 'sensors' ? I seems to be
able to execute other files in /usr/bin, and I can execute it if I give
the full pathname.

- Richard
-- 
Richard Kimber
http://www.psr.keele.ac.uk/