184.108.40.206. ...posting to a mailing list when a disposable email address is used to subscribe to the list?
You will need to create an email account configuration that lets you post from the alias address. This requires an email client that can handle multiple sending accounts.
To use the Evolution client to send email from a disposable address, add a new account under Edit->Preference with your name and the disposable email address, a receiving server type of None, and a sending server type of Sendmail. When sending a message to the list, select the disposable email address from the pull-down list labeled From in the mail composition window.