[https://bug286760.bugzilla.mozilla.org/attachment.cgi?id=413868 0.2 Release]: In the end, I did not use the TRIM_WHITESPACE() macro, because of my small understanding of how it works. Just a little bit of code is added to the msg_quote_phrase_or_addr() function. This bit of code removes trailing spaces from the address given. However, I might be at fault, because this code might not be allowed due to some RFC regulations.