Thunderbird issue or mailserver issue?

[Dan Miller]

A few days ago, one of the email accounts I checked started getting 
timeouts (at least thats what Thunderbird is saying). I've ran wireshark 
twice to see the transmission. Each time, I'm getting various packets 
with the wrong checksums. Also, at the end of the transmission I'm doing 
retransmissions requesting UIDL.

I've talked with the admin, he has rebooted the box, but I'm thinking 
there is another issue somewhere. Any ideas? Could it be me or him? (He 
says its fine on his end.)

I've looked at my installed packages, and my firewall. The only thing 
that changed on my end the day before was a new ca-certificates, which 
even after rolling back doesn't fix the issue. Any ideas?

I have tried mutt, at it does say I have mail. I use Thunderbird for two 
other accounts (including this one) and they work fine.

Dan