I have the same problem with DVD+RW and Brasero on Ubuntu 9.10. I remember having the same problem on Ubuntu 8.04, but I was able to use the CD/DVD Creator then to bypass Brasero. In Ubuntu 9.10, however, CD/DVD Creator uses Brasero to blank DVD+-RW, so I have no way to avoid this problem.
I have the same problem with DVD+RW and Brasero on Ubuntu 9.10. I remember having the same problem on Ubuntu 8.04, but I was able to use the CD/DVD Creator then to bypass Brasero. In Ubuntu 9.10, however, CD/DVD Creator uses Brasero to blank DVD+-RW, so I have no way to avoid this problem.