SIGAR 1.6.4 was just released and contains fixes for a number of bugs that we care about (see the issues that this one blocks).
http://jira.hyperic.com/browse/SIGAR-201, for which there is no corresponding RHQ issue, is also fixed in 1.6.4.
Here's another one it fixes that we care about - http://jira.hyperic.com/browse/SIGAR-187. If there's a corresponding RHQ issue, I can't find it.
Done in master branch - commit 71c80f76135eb4ae34dae2914d471044ffdfb4d9.
QA: I think an execution of the regression suite will probably suffice to test this.
Verified on JON build #154 - Revision: 10620
Installed latest JON build (build #154) and rhq-agent. There is upgraded SIGAR 1.6.4 - <AGENT_HOME>/lib/sigar-126.96.36.199.jar
Executed test automation group(s), observed execution results and verified server/agent log.
Mass-closure of verified bugs against JON.