I have some similiar situation when I tried to use xepdmgrclient in djview4. I included xepdmgrclient.h and xepdmgrclient.c in the source code.
Code:
[sbox-iLiad-oesdk: ~/djview4-4.5/src] > make
g++ -c -pipe -I.././src -I.. -pthread -I/usr/local/include -O2 -Wall -W -D_REENTRANT -DAUTOCONF -DNDEBUG -DQT_NO_DEBUG -DQT_NO_DEBUG_STREAM -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I/targets/iLiad-oesdk/usr/local/Trolltech/Qt-4.5.2/mkspecs/linux-g++ -I. -I/targets/iLiad-oesdk/usr/local/Trolltech/Qt-4.5.2/include/QtCore -I/targets/iLiad-oesdk/usr/local/Trolltech/Qt-4.5.2/include/QtNetwork -I/targets/iLiad-oesdk/usr/local/Trolltech/Qt-4.5.2/include/QtGui -I/targets/iLiad-oesdk/usr/local/Trolltech/Qt-4.5.2/include -I/usr/X11R6/include -I. -I. -o djview.o djview.cpp
In file included from djview.cpp:58:
xepdmgrclient.c: In function `sEpd* EpdInit(char*)':
xepdmgrclient.c:43: error: invalid conversion from `void*' to `_sEpd*'
xepdmgrclient.c: In function `int EpdRefreshAuto(sEpd*, int)':
xepdmgrclient.c:98: error: invalid conversion from `const char*' to `char*'
xepdmgrclient.c:98: error: initializing argument 2 of `int EpdLocalSend(_sEpd*, char*)'
xepdmgrclient.c: In function `int EpdLocalSend(_sEpd*, char*)':
xepdmgrclient.c:126: error: invalid conversion from `void*' to `char*'
xepdmgrclient.c:133: error: invalid conversion from `void*' to `char*'
make: *** [djview.o] Error 1