Why is it hard to make Qt bindings?

[drug via Digitalmars-d-learn]

There were several attempts to make Qt binding for dlang, but either 
they has failed or has been stalled. It would be nice to collect that 
experience. Considering 2.081 supports C++ special member (not all but 
majority) isn't it time to make another attempt or the problem is more 
complex?
Could you publish your experience in making Qt bindings here?