Capturing POP3(S) more thoroughly?

[Tim Landscheidt]

Hi,

my provider's POP3S support stopped working. When I set
pop3-debug to t, my Gnus 5.13 gets a nice " trace of POP
session to $HOST":

| +OK POP3 server ready <$SOMEID@$HOST>^M
| *** Fatal error: A TLS packet with unexpected length was received.
| *** Server has terminated the connection abnormally.

| Process POP exited abnormally with code 1

How can I capture ideally all dialog, but at least the
commands Gnus sends, totally ideally with some fancy
">>>"/"<<<" to differentiate between incoming and outgoing
lines so I can bug my tech support?

TIA,
Tim