Strange Thunderbird IMAP problem

I have 2 computers here running linux nd using Thunderbird for email.
One is a laptop, running Vectorlinux-4.2; the other is a desktop,
running Fedora 10 x86_64. Thunderbird is configured identically on both
to ccess to separate IMAP accounts. Until this morning, both worked
fine. Now the Fedora machine can no longer access my gmail IMAP account;
it times out without establishing the connection. My laptop can still
connect perfectly well. Did I mention they were configured identically?
There are no firewall rules blocking gmail on the desktop machine:

[root@lancre ~]# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain blocksshd (0 references)
target prot opt source destination

I can send mail from the desktop machine via gmail's smtp service, but
copying the sent message to the IMAP folder fails, because the connection
cannot be established. The mail is received properly by the laptop
machine.

WTF is going on? The only change in the system was installing Fedora's
newest kernel and rebooting, as requested by the system update applet.

# uname -a
Linux lancre 2.6.27.19-170.2.35.fc10.x86_64 #1 SMP Mon Feb 23 13:00:23
EST 2009 x86_64 x86_64 x86_64 GNU/Linux

The last mail received from gmail on the desktop machine was at 0745CST
this morning, just prior to installing the new kernel and rebooting.

I can't imagine a kernel update specifically blocking IMAP on gmail, but
I have no other clues to go on.

--

John (john@xxxxxxxxxxx)
.

Relevant Pages

  • Strange Thunderbird IMAP problem
    ... One is a laptop, running Vectorlinux-4.2; ... Now the Fedora machine can no longer access my gmail IMAP account; ... There are no firewall rules blocking gmail on the desktop machine: ... Chain FORWARD ...
    (Fedora)
  • summary on my previous post - "SSH connection problem"
    ... i can connect from desktop to laptop but not reversely. ... still no connection from laptop to desktop after that. ... UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 ... Chain FORWARD ...
    (Ubuntu)
  • Re: Wireless considerably faster one way than the other
    ... plugged into network hub. ... The Access Point is approximately 3 inches away from the laptop. ... installed it on a desktop machine and the laptop. ...
    (alt.internet.wireless)
  • Re: Wireless considerably faster one way than the other
    ... plugged into network hub. ... The Access Point is approximately 3 inches away from the laptop. ... installed it on a desktop machine and the laptop. ...
    (alt.internet.wireless)
  • Hidden files on machine sensitive external USB drive
    ... The 120 GB partition was then designated to be shared over the network that links my DeskTop to my LapTop. ... When the Hitachi HDD via USB is connected to the LapTop, one cannot use Windows Explorer on the LapTop to find the Music Directory on the Hitachi hard drive. ... one can find the Music Directory on the Hitachi Hard Drive using the DeskTop machine to examine the LapTop machine via the network connection. ...
    (microsoft.public.windows.file_system)