Tcl syntax checking support seems to have been dropped in Komodo Edit 4.3. What's the deal?
The Tcl syntax checker used in Komodo IDE and previous releases of Komodo Edit is not open source, therefore we decided to remove it from the main build of Komodo Edit as of version 4.3 and provide it as a closed-source extension instead:
http://community.activestate.com/komodo-extension/tcl-syntax-checker