why i can't send mail?
Your email came though, so apparently you can with this account. If there is another account you cannot send from, you will have to read the email bounce message, it should describe why you would be unable to send email. To work around any problems, you can subscribe to the gcc mailing list with the other account name before sending email, I think that will do the trick. There is one other way, as documented at:
http://gcc.gnu.org/lists.html
You will want to read that page under Spam blocking.
