vcloud director VcloudAdminExtension exception raised

Hi,

I'm using vcloud director sdk for java and in ImportVmAsvAppTemplate community example this exception:

Exception in thread "main" com.vmware.vcloud.sdk.VCloudException: This operation is denied.
    at com.vmware.vcloud.sdk.Response.handleUnExpectedResponse(Response.java:132)
    at com.vmware.vcloud.sdk.SdkUtil.validateResponse(SdkUtil.java:189)
    at com.vmware.vcloud.sdk.SdkUtil.get(SdkUtil.java:99)
    at com.vmware.vcloud.sdk.admin.extensions.VcloudAdminExtension.getVMWVimServerRefsByName(VcloudAdminExtension.java:199)
    at com.vmware.vcloud.sdk.samples.extra.ImportVmAsvAppTemplate.main(ImportVmAsvAppTemplate.java:117)

when I use VcloudAdminExtension class.

        // getting to the extension api. getting org, vdc, vimserver etc
        VcloudAdminExtension extension = client.getVcloudAdminExtension();

        HashMap<String, ReferenceType> vmwVimServerRefsByName = extension.getVMWVimServerRefsByName(); //com.vmware.vcloud.sdk.VCloudException RAised here

thanks in advance

luca