Activating Office SharePoint Server Publishing Infrastructure gives Access Denied Error

I was trying to activate Office SharePoint Server Publishing Infrastructure option on the MOSS Installation on my machine; it’s giving an Access Denied Error. As I was sure of the permissions, I have googled for solution. There are multiple posts over the web offering a solution for the problem. The solution was to go to IIS and make your web application run under the same Application Pool under which the SharePoint Central Administration is running and then activate the publishing infrastructure and change the Application pool back to the previous pool the web application was running. Though this solution works fine, I was not really sure of what was the problem. Further probing has led to the following findings.

• Security Account for Application pool under which the web application is running is a domain account.
• Security Account for Application pool of SharePoint Central Administration is Network Service Account.
• Changing the security account for the Application Pool (under Properties choose Identity tab select predefined option) will also give the same result as elevating the web application to run under central administration application pool.