[xml] Adding a DTD with attributes dynamically

[Marius Kjeldahl <marius kjeldahl net>]

I wish to add the DTD to a dynamically created xml document. Does anybody know 
how it is done? For instance, I want to call functions in libxml that creates 
something like:

<?xml version="1.0"?>
<!DOCTYPE ThreeDSecure [
<!ATTLIST CRReq id ID #IMPLIED>
]>
<ThreeDSecure>
...

By using xmlCreateIntSubset I get the DOCTYPE line in ok, but I can not figure 
out how to add the ATTLIST entries.

Does anybody know if this is possible, and how?

Thanks,

--
Mvh, Marius Kjeldahl