fetchmail bug ... or list bug?

[J Horacio MG <homega@ciberia.es>]

I was fearing that either procmail or fetchmail were not delivering all
mail every now and then, until now that I saw this message from
fetchmail:

fetchmail: SMTP< 354 Enter message, ending with "." on a line by itself
#*********************.*******************.************************************.*****************************.********************.***********************.*************************fetchmail:
SMTP>. (EOM)
fetchmail: SMTP< 552 Header line is ridiculously overlong
fetchmail: SMTP listener refused delivery
 not flushed
fetchmail: POP3> QUIT

Is this a fetchmail bug, or should I report this to the sender (to a
listmaster in this case).

FYI This is fetchmail release 4.6.4


TIA
-- 
Horacio
homega@ciberia.es
Valencia - ESPAÑA