Corporate firewall blocking cisession cookies

[eluser]Unknown[/eluser]
I'm sure its an enterprise-wide issue, but not sure it is a firewall and not a browser setting that the agency enforces on all its computers (they all are using IE), or some other agency-wide "security" measure? It is possible to navigate and log-in to any other non-CI site that requires session cookies or just plain old cookies and they seem to be receiving our wordpress cookies fine. One other note, as a test I changed .htaccess so that the entire site was http for users from that domain, and the issue persisted, which led me to believe it wasn't a secure versus non-secure cookie issue.