There is a new version of Sage 1.4.4 which will be compatible with Firefox 3.6.
Sage 1.3.9 was released in 17 November 2006. It is a maintenance release with several bugfixes.
pdp has discovered a vulnerability in Sage version 1.3.6 (8 September 2006). The attacker can exploit the vulnerability to inject and execute arbitrary HTML and script code in local zone by tricking a user into adding a malicious RSS feed and then viewing the content of it. See also a Secunia advisory. The vulnerabiblity was fixed in Sage 1.3.7.
Sage 1.3.5 just released by The Sage Project (19 June 2005). This is a maintenance release that provides Deer Park compatibility and fixes an Atom parsing bug.