Understanding SOAPAction in http header (Java somewhat involved)

I noticed my home router has some configuration field "TR-069 CLIENT CONFIGURATION" and some obscure address that I noticed gets resolved quite often each day. (Yes obviously to config the router remotely.. or something) But I want to see what is being sent. So wrote a very simple "web server" in Java to read in HTTP requests (the field in the router was with a normal http:// address) and print them out. (i set that field to point to my computer where the little server is running)

And im getting these:

Host: 192.168.1.2
U开发者_JS百科ser-Agent: Allegro-Software-WebClient/4.07
Accept: */*
Content-Type: text/xml; charset=utf-8
Content-Length: 2767
SOAPAction:

Was kind of hoping SOAPAction: wouldnt be empty but what does this mean, is it some deprecated feature of the router that just happens to keep going? (its a d-link ADSL Router)

There would be multiple soap envelopes in HTTP Request.

TR-069 spec says

When there is more than one envelope in a single HTTP Request, the SOAPAction header in the HTTP Request MUST have no value (with no quotes), indicating that this header provides no information as to the intent of the message. That is, it should appear as follows:

SOAPAction: