Deleting Mail From Server

I am very new to thunderbird. I guess this program is kinda nice.

I use it with webmail plugin and using pop3. I tried to use IMAP with hotmail, but I can't make it work :).

I set the program to leave message on the server until I delete them, when I delete the mail from the program, the mail is still in the email server. I thought until I delete them meant when I delete them from the program not from the email server.

After googling, I found that some say edit the config mail.pop3.deletefromserveronmove to true. However, the mail is still in the email server.

I would like to know if there is any way to delete the mail from the server when I delete the mail from the program inbox? Thanks.