Hi!
I think the hostname of the certificate has to match the hostname you are trying to reach.
So the default certificate localhost.localdom would only work, if you try to connect to vCO with localhost.localdom (it might be worth a quick shot editing the hosts-file on your wavemaker system :-)
To change the certificate on vCO to match the actual hostname of the vCO box, see here:
http://www.vcoteam.info/learn-vco/work-with-vco-over-ssl.html
http://enterpriseadmins.org/blog/virtualization/vco-appliance-and-ssl-certificates/
After chaning this, and deleting the old one and importing the new one to wavemaker's keystore it should work... Let us know! :-)
As heavy-weight workaround: You can skip using WaveMaker's webService tool, and create your own JavaService. See an example here: http://blog.mightycare.de/en/2012/06/wavemaker-spring-and-vmware-infrastructure/
PS: The example there uses the old SOAP API of vCO, but you'll get the idea (and java bindings for the new REST API from https://yourvcoserver:8281/api/docs/downloads.html
PPS: It's in German, but you can download the example project at the end of the article. If you need a translation/further discussion about this, let me know...
Cheers,
Joerg