some files cannot be found in the Linux server when I run using cron

view story

http://stackoverflow.com – I run my python scripts in a Linux server and they are run successfully when I run it on the remote terminal using ssh. But when I run the commands using a crontab file, it cannot find certain files that are installed in the server. What difference does it make when I run the scripts using cron ? The cron file is in the same directory as my python scripts. I'm using "raster2pgsql" loader that is installed in postgresql installasion folder. The error meesage is: sh: raster2pgsql: not found my cron file content is: */2 * * * * /usr/bin/env python /home/testexe/LST.py >> /home/testexe/ (HowTos)