Helpeth me please.

Here's what I'm trying to do.

Code:
#!/bin/bash
#
# This runs a daily check for suspicious activity using chkrootkit
#
SUBJ="Root Scan For $HOSTNAME on `date`"
/opt/chkrootkit-0.43/chkrootkit | mail -s "$SUBJ" user@address
It works, but chkrootkit can't exec things that it otherwise can when run directly (as in cd chkrootkit-0.43; ./chkrootkit | mail -s blah blah blah).

Code:
.
.
.
Checking `sniffer'... not tested: can't exec ./ifpromisc
Checking `w55808'... not infected
Checking `wted'... not tested: can't exec ./chkwtmp
Checking `scalper'... not infected
Checking `slapper'... not infected
Checking `z2'... not tested: can't exec ./chklastlog
Both scripts are owned by root and the entire chkrootkit dir is owned by root.

Am I calling chkrootkit the wrong way? Is it maybe that chkrootkit is a sh script and not bash? ???

Oh, and I'm launching this script as root.