Connection probs from aol.com SMTP since Tuesday morn

Since Tuesday morning (2010-05-25 09:15:28 UTC) I started noticing incoming SMTP connection problems from AOL outbound servers. Here's the most recent log entry (time is UTC):

May 26 19:55:31 weird2 sm-mta[10784]: o4QJtVTq010784: imr-db01.mx.aol.com [205.188.91.95] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA-v4

This suggests that the TCP connection is failing after EHLO. Has anyone else noticed this or other network problems that started Tuesday morning?

== UPDATE:

I turned up the log level on sendmail and noticed that AOL is disconnecting immediately after my server sends the 220 greeting.