There should not be such difference.
tested against Qt 4.7.1
in the attached test case, you can change the macro defined in mywebpage.h to see the difference.
Created attachment 78219 [details]
test case. change the macro in mywebpage.h to see the difference
Please follow http://trac.webkit.org/wiki/QtWebKitBugs when reporing bugs here (missing Qt keyword).
Please use your own address when reporting bugs. With qt-info, we have no way to ask questions. My guess is Jing did the job on this bug :)
Fixed in trunk: http://trac.webkit.org/changeset/74909
*** This bug has been marked as a duplicate of bug 51464 ***