[SOLVED] dpkg error: contains ununderstood data member

dpkg error: contains ununderstood data member

I'm trying to install a jailbreak tweak using make package install but I'm receiving this error from dpkg:

dpkg-deb: file `/tmp/_theos_install.deb' contains ununderstood data member data.tar.xz     , giving up
dpkg: error processing /tmp/_theos_install.deb (--install):
subprocess dpkg-deb --fsys-tarfile returned error exit status 2
Errors were encountered while processing:
/tmp/_theos_install.deb
make: *** [internal-install] Error 1

So as far as I can tell it isn't able to understand the .xz extension, but I'm not sure why that file is being created. Thanks for the help.

Solution

I found out how to fix it. In $THEOS/makefiles/package/deb.mk replace this line:

 $(ECHO_NOTHING)COPYFILE_DISABLE=1 $(FAKEROOT) -r dpkg-deb -b "$(THEOS_STAGING_DIR)" "$(_THEOS_DEB_PACKAGE_FILENAME)" $(STDERR_NULL_REDIRECT)$(ECHO_END)

with this line:

$(ECHO_NOTHING)COPYFILE_DISABLE=1 $(FAKEROOT) -r dpkg-deb -Zgzip -b "$(THEOS_STAGING_DIR)" "$(_THEOS_DEB_PACKAGE_FILENAME)" $(STDERR_NULL_REDIRECT)$(ECHO_END)