How to invoke a LANDesk MBSDK method using a HTTP POST including credentials

I want to do an automatic MBSDK method.

Therefore I need to include the username and the password in the HTTP request.

Does anyone know what the format is how to do that?

I tried http://USERNAME:PASSWORD@CORESERVER/MBSDKService/MsgSDK.asmx/AddComputerEx?deviceName=DEVICENAME&type=Computer&ipAddress=1.1.1.1&IPName=DEVICENAME&macAddress=AB-CD-EF-12-34-56&assetTag=HDV2LV1

But that doesn't work.

Any ideas?