Here are the steps on how to reproduce this bug report:

1. Add a Projects gadget in the Dashboard
2. Try to mass create projects until around 420+ projects
3. Click on the 'Dashboard' main tab
4. It will take some time to load until a javascript pop-up error appearing as follow:
   

If you click on 'No', then it will continue to load normally. However, if you click on 'Yes', you will be seeing an error like:

Consequently, the Javascript will be disabled.

This problem only happens in IE7 but it works in Firefox 3.6.13 and IE8.