pop 110/995, imap 143/993 ?

[Sebastian Arcus]

On 21/08/17 10:37, Gedalya wrote:
> On 08/21/2017 07:28 AM, voytek at sbt.net.au wrote:
>> is there a 'preferred way'?  should I tell users to use 143 over 993 ? or
>> 993 over 143? or?
> There is no concrete answer. There are various opinions and feelings about this.
> The opinion againt 993/995 is that these are not standard ports, 

Out of curiosity, is there a source for this? It's the first time I hear 
that 993/995 are not standard ports - and searching on the Internet, I 
can't find any evidence to back it up? Also, pretty much all email 
software has been using them for the past 20 years or so. It seems like 
a curiously high rate of adoption for a non-standard :-)