### Description

When configuring as a global configuration the following parameters:

user_agent_header="User-Agent: Company-Product1-1.0.0" server_header="Server: Company-Product1-1.0.0"

I expected to have in every responses the Server header and in every requests the User-Agent header. But I'm only see the Server header in the first 100 response and the User Agent header is never sent in the responses.

#### Log Messages

I don't have any error message in the log.

#### SIP Traffic

- First response to an INVITE with Server header. 

- First resquest without User-Agent header: 

- Second response without Server header: 

### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` kamailio-4.4.5 ```

* **Operating System**:

``` Linux test200 2.6.32-642.15.1.el6.x86_64 #1 SMP Fri Feb 24 14:31:22 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux ```

Is there something that I'm doing wrong?

Thanks