[Mailman-Users] missing posts

[marioca]

Can anyone help out with this problem.  We have had subscribers missing posts in the past and it has happened again. Here is the most recent sequence of events in which subscribers did not get which post:

1. Earthlink subscriber posts to list
2. VTR.net (from Chile) subscriber responded to #1
3. Mindspring subscriber received post by #2 but not #1
4. Hotmail subscriber received #3 post but not #1 and #2

Has any one else experienced this or have an idea about what is causing certain people not to get certain messages?

Thanks.
marioca