Perforce: How can I back out a changelist across an integration?

Question

At my company we make a new branch/folder for every release. In the 1.0 folder, there is a changelist that introduced a bug. Unfortunately, 1.0 is shipped and we are working on 2.0. How can I take the changes in the 1.0 changelist and revert them only in the 2.0 folder?

I can think of the following solution.

1. Back out that revision in 1.0
2. Submit it
3. Integrate between 1.0 and 2.0 to apply the changes made by backing out.

However, the 1.0 branch should be locked since it is shipped. Can I do this without submitting a changelist to 1.0?