XML entities do not render out

I've reported this before ... still broken, months later.

I have a lot of common links stored in an external entity, i.e.:

<!DOCTYPE document [
<!ENTITY % common-links SYSTEM "../common/links.xml">
%common-links;
]>
<document>

links.xml contains a bunch of stuff like this:

<!ENTITY _module '<code>module</code>'>
<!ENTITY module '<a href="&projectroot;descriptor.html#module">&_module;</a>'>

<!ENTITY _implementation 'implementation'>
<!ENTITY implementation '<a href="&projectroot;descriptor.html#implementation">&_implementation;</a>'>

My source .xml file looks like:

The root element of the descriptor is the &module; element.

But renders out like:

The root element of the descriptor is the <A
href="descriptor.html#module"></A>element.

I've tried a number of things such as removing the <code> and </code> from &_module; or changing the &_module; reference itself to just module. Same result.

However,

<!ENTITY module '<a href="&projectroot;descriptor.html#module"><module></a>'>

renders as:

The root element of the descriptor is the <A
href="descriptor.html#module"><module></A> element.