Error when trying to delete a page layout in MOSS: This item cannot be deleted because it is still referenced by other pages

This info comes from: http://www.katriendg.com/aboutdotnet/Default.aspx?m=1&y=2007

After deactivating & uninstalling a feature (CustomMasterPages) and reinstalling it again the original page layouts & masterpages still remain in the "Master Page and Page Layout Gallery".

Trying to manually delete the files from the gallery gives the following error:

"This item cannot be deleted because it is still referenced by other pages"

The problem is mentioned in the following KB article:

http://support.microsoft.com/?kbid=926812

The KB proposes changing the master page properties to Hidden.

Alternative workaround:

• Create a new sub-folder in the master page gallery
• Move the page layout to the new folder using SharePoint Designer
• Delete the complete folder