Site Actions button is disabled

I have a SharePoint 2007 site where the Site Actions button is disabled only in IE. When a user first arrives to the page the Site Actions button 开发者_运维知识库works,but when he/she refreshes the page the Site Actions button is disabled, but if he/she does a refresh for the third time the Site Actions button works again? Any ideas...

UPDATE I am using jQuery-1.6. What I is that once I take that reference out I no longer get error.

One way to debig this is to use Web Developer Tool bar in IE 8+ and then check the style for "Site Actions". It will give you some ideas about what is happening.