Hi Mike, sorry for delay... im testing it in my lab machine and no detect
rare things in session db:

Test NX user "admuser" conected:

3437|admuser-50-1418900890_stDMATE_dp24|50|ubuntu|R|2014-12-18T12:08:10|1f4e671c91f743d46ac52d4b4ff8ee93|192.168.88.214|30001|30002|2014-12-18T12:08:12|admuser|32|30003|

Second NX user "test" connect to a desktopsharing session:

3437|admuser-50-1418900890_stDMATE_dp24|50|ubuntu|R|2014-12-18T12:08:10|1f4e671c91f743d46ac52d4b4ff8ee93|192.168.88.214|30001|30002|2014-12-18T12:08:12|admuser|115|30003|
4997|admuser-51-1418900993_stS0XSHADadmuserXSHADPP50.0_dp24|51|ubuntu|R|2014-12-18T12:09:54|f0ad3b00f15dd59a80a1e6572790a0b8|192.168.88.214|30004|30005|2014-12-18T12:09:55|admuser|11|30006|

Second NX user disconect before few minutes:

3437|admuser-50-1418900890_stDMATE_dp24|50|ubuntu|R|2014-12-18T12:08:10|1f4e671c91f743d46ac52d4b4ff8ee93|192.168.88.214|30001|30002|2014-12-18T12:08:12|admuser|240|30003|

Regards!