dcop function are normal class function which can be called from another program. So, if the functions are documentated, they are in the API documentation.
For Kopete, I did a grep for "k_dcop". The functions are defined in the following files:
- kopete/kopeteiface.h
- kopete/kimiface.h
- libkopete/connectionmanager.h
- libkopete/clientiface.h
- plugins/statistics/statisticsdcopiface.h
- plugins/smpppdcs/smpppdcsiface.h
You can view the files with
http://websvn.kde.org/branches/KDE/3.5/kdenetwork/kopete/
For libkopete, there are api references at
http://developer.kde.org/documentation/l…libkopete/html/
The functions which come from libkopete are most likely described there.