Related:
How can I add a program to the context menu of all files?
How can I add an icon to my custom context menu item in Windows 7?
The first linked question covers how to add a custom context menu option for all files. This has been tested in Windows XP and Windows 7. The second question is about adding an icon alongside that menu item. The answer provided works in Windows 7, but strangely not in Windows XP. Since the question was tagged as windows-7, and since XP seems to be an odd exception for this, I figured I'd spin this question off onto its own.
I know this should be possible in Windows XP, because programs like Notepad++, WinZip, and some Antivirus applications have their icons in the context menu. However, their context menu items appear to be part of a registry key path (or series of keys) with which I'm not at all familiar.
So I'd like to know how can I add an icon to a context menu item created using the method in the first linked thread here? Or, if that's impossible (or improper), what's the "right" way to create menu items similar to the examples I've given?