Forum .LRN Q&A: Re: invalid command name "Class"
I don't have experience with dotLRN. Maybe this is an xotcl installation error. See: http://openacs.org/forums/message-view?message_id=436606
Because I installed xotcl automatically, I supposed the installation should be complete, but it wasn't.
The package "aolserver4-xotcl" wasn't installed so the problem has been solved only by installing it.
Thanks again. Your advice has been right.