Terrible IE performance under 6.0.4

[Vladimir]

For some reason I'm finding that IE 8 and 7 perform very poorly with ZWC after we've upgraded to 6.0.4. Running from the same machine connected to the same account, FF works just fine with no delays, but IE hangs trying to autocomplete address field and often fails, takes forever to send a message after send button was pressed, sometimes throws errors like this one:

Message: The remote server machine does not exist or is unavailable
Line: 6367
Char: 1
Code: 0
URI: https://rumail.rutgers.edu/zimbra/js/NewWindow_2_all.js.zgz?v=091214175450

I'm not seeing anything on the server side, and as mentioned FF works just fine. Has anyone else seen this?

[uxbod]

May be linked to Bug 40189 - Email Zimlet throws JS expn in IE8 during loading. What skin are you using ? If you change the script does it work any better ?

[Vladimir]

I've tried multiple skins and it seems to be an issue that crops up after a bit of use.

[uxbod]

Hmm, memory leak in IE8 ? if you shut IE8 down and then restart does it start to behave again ?