Like I posted in your Aperture2Gmail thread:
In the past, connectivity issues like this one were usually due to
proxy settings or poorly behaving DNS. Are you by any chance behind a
proxy or using a third party DNS server?
I'll be releasing iPhoto2Gmail 1.1 later this weekend, give that a try
and let me know if you continue to have trouble.
Thanks for taking the time to send feedback.
JI