The new version of VAX (10.4.1619.0) messes up my visual studio integration on my Visual Studio 2005 SP1 . The problem remains when I disable VAX but is solved when I uninstall it.
Here are two screenshots attached showing QtDesigner integrated in VS. - nobug.jpg is taken with no VAX installed - bug.jpg is taken with VAX installed
I did not have any problem with the last VAX build I had (1561).