SpamAssassin and POSTFIX script wrapper problem


I have recently been the victim of a number of spam attacks so I have beefed up the spam config. I found a tutorial online which gets SpamAssassin to scan everything that goes through the postfix server. See link below for tutorial I followed.

This script works for anything that is send via the apache web server which is great but whenever a user logins to the postfix server from there email client i get the following error.

Apr 29 11:11:41 fantasticsolutionsdns postfix/pipe[11338]: 292B726B0052:,, relay=spamchk, delay=19234, delays=19234/0.1/0/0.02, dsn=4.3.0, status=deferred (temporary failure. Command output: pipe: fatal: pipe_command: execvp /usr/local/bin/spamchk: Permission denied )

Can anybody give me any guidance on how I can change the permissions so I don’t get this permissions problem.