[simbr]

Well, it's definately not the hudd proxies as they all seem to reach ebay ok, but then if it's working in firefox it does suggest a problem with IE anyway.
Have you run any anti-spwyare programs lately?
As a rough check you could try temporarily disabling browser extension:
Click "Tools" then "Internet Options"
Go the the "Advanced" tab.
Untick "Enable third-party browser extensions"
Click OK, then close all browser instances
Try the site again.
(remember to retick the box otherwise you may lose some functionality)

Another thing you can try is a repair of IE, as I assume since you're still on 5.5 that you have Win9x/ME:
Click "Start", then "Settings" then "Control Panel"
Double click "Add/Remove Programs"
Scroll down the list to "Microsot Internet Explorer 5.5 and Internet Tools"
Click the remove button then select the option "Repair Internet Explorer"
Of course, upgrading to IE6 wouldn't hurt either.