When ever trying to install a new application, it get the following error:

E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

So, as it suggests, I run apt-get -f install...no good, I get this error:

dpkg: error processing /var/cache/apt/archives/libxcursor-dev_1.0.2-2_i386.deb (--unpack):
trying to overwrite `/usr/X11R6/include/X11/Xcursor/Xcursor.h', which is also in package xlibs-dev
Errors were encountered while processing:
/var/cache/apt/archives/libxcursor-dev_1.0.2-2_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Any suggestions? I am new to debian, have been using linux off and on for about three years, still consider myself a beginner. I upgraded my machine to unstable after performing a knx-hdinstall using the directions on debian.org . Any help would be appreciated.-Ryan