[horde] Can't create folders and not not save messages sended

[Indalecio José Trujillo Pichardo]

Have horde+imp running as webmail use qmail+vpopmail+courier-imap, have 
two troubles
1. if need to create a folder show this message "The folder 
namefoldertocreate was not created, This is what the server said:invalid 
mailbox name.", not understand why occour this.

2. when compose a new message, write de message, have the check "save a 
copy in sent-mail" active send the mail, but no save the email sended by 
the problem 1.

Thank