User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Tablet PC 1.7; .NET CLR 1.0.3705; .NET CLR 1.1.4322; InfoPath.2; .NET CLR 2.0.50727) Build Identifier: version 184.108.40.206 (20071209) from Fedora development (thunderbird-220.127.116.11-2.fc9.i386) I have an email message in an imap folder which has another email message as an attachment. I double-click on the attachment and then select Message > Edit Message As New. Thunderbird fails to pop up a new compose window with the message in it, and instead displays an error dialog which says, "An error occurred while creating a message compose window. Please try again." Reproducible: Always Steps to Reproduce: See above. Actual Results: See above. Expected Results: See above.