Occasionally, when I'm checking in a bunch of files individually (say each file has a distinct change), I might accidentally do something dumb like a svn commit without a filename, and suddenly everything's checked in. Sigh. So now the commit message is for a particular one-file change, and now the rest of the files have this comment. Sigh again.
If you're in control of the repository, you can put the proper log message into a text file, and hack your repository (assuming oop.txt has the new comment contents, and it was revision 285 that accidentally got All The Things):% cd parent-directory-of-repository % svnadmin --bypass-hooks setlog ./svnroot -r 285 /tmp/oop.txtIf your repository is more than "just your own thing", you might want to follow the more complicated instructions at at the Subversion FAQ.