>> I specifically asked not to make this the default.
>>

In <http://bugs.gnu.org/26102#39> you asked not to remove the POP source 
code. Sorry, I must have missed where you specifically asked not to make 
--without-pop the default (which is a different issue).

> ..then you should fix also the configure warning... [*] 

I installed the attached patch to try to improve the 'configure' 
diagnostics. Please feel free to revert or improve it if you think the 
patch makes this confusing area even more confusing.