Spamcop failing to detect true originating IP

Hiyas. I'm no antispam maven and don't have much ambition to become one, 
but I've been using the Spamcop website sporadically over the last few 
months to report a bunch of spams with originating IPs not already in 
the SC blocking list. About 5 days ago the SC site seems to have 
changed. Apparently the parser progs are treating my pasted spams 
differently. I'm using the exact same method (in Thunderbird, View, 
Message Source, Ctrl-A, Ctrl-C, paste into SC website spam reporting 
input box), but now all my submissions come back with a message like "No 
source IP header found - cannot proceed". Most of these spams have 
spoofed senders but the real originating IP is plain to see in the 
second block of headers. Why is SC suddenly unable, or suddenly 
unwilling, to see them?

I quickly set up Mailhosts just now but the problem remains. I guess 
I'll have to read more to see if my Mailhosts setup is correct, but like 
I said I don't plan to get too deep into this. I'm on vacation from 
heavyduty putering for at least a year.

Anyway, just thought I'd report this in case anyone at SC needs an 
additional tip-off on stuff happening out here in userland.

--
wsk