Errors using IE7 and IE6 with theme builder 3.3.5

I'm using Confluence 3.0.2 and them builder 3.3.5. The plugin file I installed was adaptavist-plugin-themeBuilder-3.3.5-conf210.jar.

When I attempt to use the plugin, such as going to the confluence admin console -> theme builder -> builder administration, the page loaded in IE7 with errors. All I see are the tabs but I can't click on anything. There is a debug message that doesn't help, and If I click on OK and it disappers I still can't click on any of the tabs.

This also happens if I change any global space to the adaptavist theme builder and try to make a new theme.

Are there compatability problems with IE7? I've tried IE6 as well with the same outcome. Unfortunately in my workplace I'm locked to IE only so have not been able to test with any other browser.

How can I either fix, or workaround this problem?