Upgrade stable -> testing -- with errors

I may have just shot myself in the foot, but I decided to go ahead and upgrade my wife's machine. It was running stable (lenny atm) and I wanted to get it to testing. Its running trinity as well. So I updated the apt-conf to APT::Default-Release "testing"; (My base sources.list includes links for all three releases), updated the trinity list from the lenny one to the squeeze one (the ppa format), and I ran aptitude update; aptitude full-upgrade. Things went well for about 30 minutes, then crashed. Now I am getting [root@galaxy archives]# dpkg --configure -a Setting up menu (2.1.41) ... update-menus: symbol lookup error: /usr/lib/libstdc++.so.6: undefined symbol: _ZNSt8messagesIcE2idE, version GLIBCXX_3.4 dpkg: error processing menu (--configure): subprocess post-installation script returned error exit status 127 Setting up python2.6 (2.6.6-8+b1) ... update-menus: symbol lookup error: /usr/lib/libstdc++.so.6: undefined symbol: _ZNSt8messagesIcE2idE, version GLIBCXX_3.4 dpkg: error processing python2.6 (--configure): subprocess post-installation script returned error exit status 127 dpkg: dependency problems prevent configuration of libpython2.6: libpython2.6 depends on python2.6 (= 2.6.6-8+b1); however: Package python2.6 is not configured yet. dpkg: error processing libpython2.6 (--configure): dependency problems - leaving unconfigured Errors were encountered while processing: menu python2.6 libpython2.6 and I can't get past the undefined symbol. Can anyone suggest what I need to get this done? Especially since I didn't warn my wife what I was doing? Thanks, --b