I'm new to Linux so i don't know if this is a bug or something that i can easily fix.

when i enter the command: apt-get upgrade

I get this error message:

dpkg: error processing /var/cache/apt/archives/kismet_2008-05-R1-4_i386.deb (--unpack):
trying to overwrite `/usr/bin/kismet', which is also in package kismet-newcore
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Processing triggers for menu ...
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)

Any advice, suggestions, or fixes would be greatly appreciated.