Can you check the sysobjectid of this WAAS?
If it is : OID:.1.3.6.1.4.1.9.1.957, it is supported in LMS 3.1 provided you have the CE500 package version 5.1 installed.
You can also go to the following link and download the packages manually:
http://www.cisco.com/cgi-bin/Software/Tablebuild/doftp.pl?ftpfile=cisco/cw20
00/patches/rme/CE500.RME42.v5-1.zip&app=Tablebuild&status=showC2A
If you download the package from the link above, it will include a pdf file
with the instructions of how to apply it.
Once you install the package please go to Common Services> Software Center>
Device Update. Right next to where is says "Resource Manager Essentials",
there should be a number, please click on that number. You will get another
page, please use the filter option. Please filter by sysObjectId, and use
the following value to filter it: 1.3.6.1.4.1.9.1.957.