Something

export OTRSUSER=otrs
useradd $OTRSUSER || :
useradd apache || :
groupadd apache || :
$RPM_BUILD_ROOT/opt/otrs/bin/SetPermissions.sh $RPM_BUILD_ROOT/opt/otrs $OTRSUSER apache apache apache



export OTRSUSER=otrs
echo -n "Check OTRS user (/etc/passwd)... "
if cat /etc/passwd | grep $OTRSUSER > /dev/null ; then
    echo "$OTRSUSER exists."
    # update home dir
    usermod -d /opt/otrs $OTRSUSER
else
    useradd $OTRSUSER -d /opt/otrs/ -s /bin/false -g apache -c 'OTRS System User' && echo "$OTRSUSER added."
fi