warning, checksum sector overwritten

[scythefwd]

I know the tool most recommended for making our images is magiciso, but I used my copy of nero to make a nrg of my disk.  Looking at my log, I see "Warning checksum sector overwritten".. whats the cause of this.  I dont usually see this when I use magic iso.. is it just due to it being nero and dero doing its own little thing?

[scythefwd]

Update.. appears to have only happened on first run..