Hey Tom :)

Here is my 10 min hack to this:

# diff observium_installscript.sh orig_observium_installscript.sh
9,47d8
< function remoteagentinstall {
<     echo -e "\nPlease enter the remote host you would to install to:${NC}"
<     read remote_srv
<     echo -e "Please enter the username for ${remote_srv}:${NC}"
<     read remote_user
<     echo -e "${GREEN}Installing additional packages...${NC}"
<     ssh -Cl ${remote_user} ${remote_srv} "apt-get -qq install -y xinetd snmpd libwww-perl libsnmp-extension-passpersist-perl"
<     scp /opt/observium/scripts/observium_agent_xinetd ${remote_user}@${remote_srv}:/etc/xinetd.d/observium_agent_xinetd
<     ssh -Cl ${remote_user} ${remote_srv} "service xinetd restart"
<     scp /opt/observium/scripts/observium_agent ${remote_user}@${remote_srv}:/usr/bin/observium_agent
<     ssh -Cl ${remote_user} ${remote_srv} "mkdir -p /usr/lib/observium_agent /usr/lib/observium_agent/scripts-available /usr/lib/observium_agent/scripts-enabled"
<     scp -r /opt/observium/scripts/agent-local/* ${remote_user}@${remote_srv}:/usr/lib/observium_agent/scripts-available
<     ssh -Cl ${remote_user} ${remote_srv} "chmod +x /usr/bin/observium_agent && \
<     ln -sf /usr/lib/observium_agent/scripts-available/dmi /usr/lib/observium_agent/scripts-enabled && \
<     ln -sf /usr/lib/observium_agent/scripts-available/apache /usr/lib/observium_agent/scripts-enabled && \
<     ln -sf /usr/lib/observium_agent/scripts-available/mysql /usr/lib/observium_agent/scripts-enabled"
<     scp /opt/observium/scripts/distro ${remote_user}@${remote_srv}:/usr/bin/distro
<     ssh -Cl ${remote_user} ${remote_srv} "chmod +x /usr/bin/distro"
<     scp /opt/observium/scripts/ifAlias_persist ${remote_user}@${remote_srv}:/usr/bin/ifAlias_persist
<     ssh -Cl ${remote_user} ${remote_srv} "chmod +x /usr/bin/ifAlias_persist"
<
<     echo -e "${GREEN}Reconfiguring ${remote_srv} snmpd${NC}"
<
<     snmpcommunity="$(< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-15};echo;)"
<
<     echo "agentAddress  udp:0.0.0.0:161" > /tmp/snmpd.conf
<     echo "view all included .1" >> /tmp/snmpd.conf
<     echo "rocommunity $snmpcommunity" >> /tmp/snmpd.conf
<     echo "extend .1.3.6.1.4.1.2021.7890.1 distro /usr/bin/distro" >> /tmp/snmpd.conf
<     echo "pass_persist .1.3.6.1.2.1.31.1.1.1.18 /usr/bin/ifAlias_persist" >> /tmp/snmpd.conf
<     scp /tmp/snmpd.conf ${remote_user}@${remote_srv}:/etc/snmp/
<     ssh -Cl ${remote_user} ${remote_srv} "service snmpd restart"
<
<     echo -e "${GREEN}Adding ${remote_srv} to Observium${NC}"
<     /opt/observium/add_device.php ${remote_srv} $snmpcommunity
<     echo -e "${GREEN}DONE! UNIX-agent is installed and ${remote_srv} is now monitored by Observium${NC}"
<
< }
<
133,134c94
< echo "5. Remotely Install the UNIX-Agent (snmpd-config will be overwritten)"
< echo -n "(1-5):"
---
> echo -n "(1-4):"
138,141d97
<    exit 1
< fi
< if [ $observ_ver = 5 ]; then
<    remoteagentinstall

Tested on a single machine - for now :)

Cheers !