While I was pondering if I should drop the tclcurl package and get it removed from Debian Christian Werner from Androwish (a Tcl/Tk port for Android) started to fix the open bugs. Thanks a lot Christian!
I've now uploaded a new TclCurl package to unstable based on the code in the new upstream repository plus the patches from Christian. In case you're one of the few TclCurl users out there please try the new package.
I'm still pondering if it's worth to keep the package. For the last five years or so I could get along with the Tcl http module just fine and thus no longer use TclCurl myself. In case someone would like to adopt it just write me a mail, I'd be happy to give it away.