What version?
Was there mention of this on the bug list (here)?
You need to either upgrade or downgrade :)
Also, you need to turn on the verbose setting, and reproduce a session that generates the error from start to finish (from bash$ cpanp to cpanp>q) and make sure you report your settings (and send a copy of the report to cpanplus-bugs).
MJDsays "you can't just make shit up and expect the computer to know what you mean, retardo!"