Is it possible to set up my Spamcop email to check mail on a server that uses non-standard ports? For example, my cable internet provider uses SSL & port 995 for POP3...

From my perspective, if it isn't available in your preferences/handling screens, I'd think not. But again, I don't speak for JT.

Some email programs DO let you change the ports that are used for sending (SMTP - normally port 25) and receiving (POP3 - normally port 110) email - I am pretty sure Outlook / Outlook Express both do.

If the program does not have a box you can change the port in try changing the POP3 server host name - for instance if it now says:

pop3.your-isp.com

Try changing it to - pop3.your-isp.com:new-port-number - for example:

pop3.your-isp.com:993

Sure, you can change your end of things to try to connect with any port ... but it's the port set to listen for incoming traffic of the correct type at the other end that's crucial.

It is interesting how the same question (or varriation of the same question) pops up at about the same time in different places
see http://forum.spamcop.net/forums/index.php?showtopic=2060

From what I have tested, it appears the that only ports used by SpamCop are the standard ports:
110 for POP3
143 for IMAP
25 for SMTP (only allowed if sending from within the web mail interface)

Inserted Edit based on reply by Wazoo

The standard SSL port is 995
Note when I use port 994 I do get a warning that the security certificate does not match the internet address, but one click will set that aside until the next log in.

I'm not overwhlemed by the search tool in this thing, so had to go through my old e-mail .. finally found this .. not a direct answer, but possibly some bearing on things? http://forum.spamcop.net/forums/index.php?showtopic=1579

The "Use SSL" Checkbox in "POP Configuration" is used to have the SpamCop Email System POP from your other MSP using SSL on your behalf.

And this uses port 995. This is working for me with Gmail which requires port 995 and SSL for POP3 collection.