An implementation of Tcl in parrot. (Note: the parrot node contains a more up to date discussion of partcl than this node.)
Apparently, the ParTcl code is part of the parrot distribution.
During October, 2007 http://www.parrotcode.org/languages/ says that ParTcl is a from scratch implementation of a Tcl 8.5 compiler that passes 25% of the tcl test suite. ParTcl doesn't yet run enough Tcl to use the tcltest extension.
See http://www.parrotcode.org/source.html for more details.