I used Fiddler to apply a "man-in-the-middle" approach to sniffing SSL traffic and the application started working again with Fiddler in place between IE6 and Oracle Web Cache. This proved that the problem was in the SSL communication between IE6 and Web Cache.
Furthermore, turns out that Web Cache was recently upgraded from 10g to 11g. Rolling back to 10g makes the problem go away, so this is a confirmed server config issue.
I'll post the actual solution once Operations guys figure it out.
either way you should not use IE6... its outdated and unsupported by Microsoft.