I'd have to verify it, but from the earlier posts and yours the problem is the WSDL files on the ESXi host itself.  If you use the WSDL files from the SDK packages, you won't have this issue.

This explains why the Java, Perl and other toolkits are not encountering this error, but why you'd have issues with a non-VMware SOAP package that pulls directly from ESXi is raising these errors.

I would try to include the WSDL as part of the tool instead of attempting to load it at runtime from the ESXi host.  I'm assuming that against vCenter this isn't an issue, or it likely would have come up before.  However, it should probably be tested against vCenter as well.