I messed around with kopete for a ling time, and i finally gave up... now i use aMSN, it compiled without any problems.
I registered to thank you for the suggestion, kopete is finally compiling for me without errors. I found that the line in kopete-0.10.1/doc/Makefile that starts with TOPSUBDIRS= only had the three words doc, kopete and po. The line SUBDIRS = had all of the other languages listed, and it was that line that was causing the errors.