One way to merge in these changes is to pull them into a local branch for review, verifying the changes and then merge to back to master.

# Check out a new branch for integration
git checkout -b merge-requests/451

# Fetch the merge request into this branch
git pull \
  git://gitorious.org/qt/qt.git \
  refs/merge-requests/451

# Show the commits, assess they are okay
git log --pretty=oneline --abbrev-commit 4.6..merge-requests/451

# To apply the changes to your branch:
git checkout 4.6
git merge merge-requests/451
git push origin 4.6