Capitel v3.43 (2003/01/14) is now open source software.
The source code is available at:
Hobbes: http://hobbes.nmsu.edu/h-search.php?sh=1&button=Search&key=capitel-src.zip
or clone it or fork it from: https://github.com/OS2World/APP-COMM-Capitel
"CapiTel is a multi-threaded 32-Bit Answering Machine. There are graphical and text-mode versions available for OS/2 (ISDN CAPI 1.1 and CAPI 2.0) and Windows 95, 98, Millenium, NT 4.0 and 2000 (ISDN CAPI 2.0). A list of supported languages and the latest versions themselves can be found in the files section."
Now it is released as open source software under the GNU GPL license.
More information about Capitel at:
http://www.os2world.com/wiki/index.php/Capitel
Thanks to Werner Fehn for turing it open source.