MTOM - test file content

I've got a webservice (running in jBoss 7.4) that's using MTOM to receive files.

The client (another application. SoapUI for testing) sends the file and we receive it.

What's the best approach to create a test that does a request with a file attached to it and after that do a check if the attachment was really received (compare the binary data).

How should I do this?