Some days ago one of my MOSS 2007 WCM sites faced up with an "Object Required" Java Script error while a content editor tried to drag & drop a Web Part in a custom Web Part Zone. Usually this sets the index of the Web Part in this Zone.
All right.. I tried to debug the problem with Visual Studio. The Debugger gave me the information about a missing offset in function “MSOLayout_GetRealOffset”, but I wasn't able to figure out what the reason for this behavior could be. After the provisioning of a new Site with the Standard Master Pages and Style Sheets applied, the error didn’t appear anymore. This means that it had something to do with my custom Styles I applied.
Step by step I reapplied my CSS and discovered that the error only appears when I apply the custom styles for my WebPart Zone Holder Divs.
In my CSS I had defined the property: “position: relative”, which caused the error.
You should use no other position definitions than “position: static”. This is the only way it works.
Drag & Drop anyway just works in Internet Explorer, but to miss this functionality is indeed not user friendly.