I have a doubt about the flag 16 used in nat_uac_test() belonging to the module NATDETECT.

In the documentation, the following is stated : 

16 - Test if the source port is different from the port in the “Via” header

I have some situations that I receive a request from port 5060 and the Via Header contains no port. I think it probably assumes that it is the default port.  

Will this situation trigger the "16" flag ? 

Thanks in advance, 

Cheers