One reference that appeared in the article only in a truncated form is the first one, to the Jacl press release. You're better off starting here. A reference that didn't make it into the article at all is John Ousterhout's What's New With Tcl?.
Steve Ball has generously made available on-line the chapter on Jacl and Tcl Blend from his forthcoming book.
Christopher Hylands posted a valuable page of corrections and observations regarding TclBlend within a couple days of its release. Also, Bob Jackson has made a particular point that the Solaris flavor requires the Native Threads Pack be added to a JDK 1.1.4 installation. Scott Stanton of Sun followed up with his advice.
Ioi Lam started the first home page for Jacl and mailing list (to subscribe, send mail to "majordom@xpi.com" with body "subscribe jacl-list your_email_address") while still a student at Cornell.
There are a few other Java-Tcl initiatives beside those emanating from SunScript.
I'm in the middle of re-writing my Java and Tcl references.
The one language which is the closest current competitor to Jacl is not JavaScript, or even Python [explain more], as a number of readers have wondered. It's the remarkable achievement of NetREXX.
We touched on a few other Jacl points in replying to letters to the editor concerning the original article. We've also written specifically on Tcl Blend.
Cameron
Laird's personal notes on Jacl and Tcl
Blend/claird@phaseit.net