This has been broken for a while, maybe nobody has reported it?
When you go to Menu>Preferences>Install Components and try to install something, nothing happens.

Today I decided to look into it, and found that the problem is actually in /usr/sbin/checkinstall.

This patch fixes it (at least for me):
Code:
# wget -O - http://dl.dropbox.com/u/17126237/checkinstall.patch | patch -p0
These are the contents of the patch file for those interested, only one line is changed:
Code:
--- /usr/sbin/checkinstall.orig	2009-02-07 18:59:59.000000000 +0000
+++ /usr/sbin/checkinstall	2011-08-06 21:10:30.936666664 +0000
@@ -103,7 +103,7 @@
  type -p Xdialog >/dev/null 2>&1 && exec Xdialog --title "'"$TITLE"'" '"$ICON"' --msgbox "'"$FAILED"'" 10 55
 fi' >"$TMP"
 chmod 755 "$TMP"
- ${XSHELL[@]} "$TMP"
+ "${XSHELL[@]}" "$TMP"
  rm -f "$TMP"
 }
Hopefully somebody finds this helpful