Azure Error: No Configuration Set should be specified while using a VMImage with a specialized OS Disk Configuration

I'm new to Azure and only started VM's from the Web interface. Now I want to start some VMs with the CLI but I can't start a VM on the command line using the following command:

azure vm create --vm-size extrasmall --ssh --ssh-cert ~/.ssh/Talentwunder2.pem --no-ssh-password --location "South Central US" tw-cloud-2 tw-image-v1-20140808-441581 azureuser

I get the following output on the shell (MacOS btw.):

info:    Executing command vm create+ Looking up image tw-image-v1-20140808-441581                               + Looking up cloud service 
info:    cloud service tw-cloud-2 not found.+ Creating cloud service                                                       + Configuring certificate                                                      + Creating VM                                                                  + Deleting cloud service
error:   No Configuration Set should be specified while using a VMImage with a specialized OS Disk Configuration. 
info:    Error information has been recorded to azure.err 
error:   vm create command failed

and azure.err has the following message:

Wed Aug 27 2014 23:18:25 GMT+0200 (CEST):
{ [Error: No Configuration Set should be specified while using a VMImage with a specialized OS Disk Configuration.]   
code: 'BadRequest',   
statusCode: 400,   
requestId: 'c398d47fdc71039a9ca1a3a1bb197fd4' } 
Error: No Configuration Set should be specified while using a VMImage with a specialized OS Disk Configuration.
    at Function.ServiceClient._normalizeError (/usr/local/lib/node_modules/azure-cli/node_modules/azure-common/lib/services/serviceclient.js:785:23)
    at /usr/local/lib/node_modules/azure-cli/node_modules/azure-common/lib/services/filters/errorhandlingfilter.js:44:29
    at Request._callback (/usr/local/lib/node_modules/azure-cli/node_modules/azure-common/lib/http/request-pipeline.js:109:14)
    at Request.self.callback (/usr/local/lib/node_modules/azure-cli/node_modules/request/request.js:129:22)
    at Request.EventEmitter.emit (events.js:98:17)
    at Request.<anonymous> (/usr/local/lib/node_modules/azure-cli/node_modules/request/request.js:873:14)
    at Request.EventEmitter.emit (events.js:117:20)
    at IncomingMessage.<anonymous> (/usr/local/lib/node_modules/azure-cli/node_modules/request/request.js:824:12)
    at IncomingMessage.EventEmitter.emit (events.js:117:20)
    at _stream_readable.js:920:16

I don't get the error message, Google is no help and I think I did what the documentation (http://azure.microsoft.com/de-de/documentation/articles/command-line-tools/) wants? Any ideas?

BtW: I created the used VM image via the Web interface from a running system and can start machines on the web interface without any problems.