diff --git a/Library/Homebrew/caveats.rb b/Library/Homebrew/caveats.rb
index 1df2e26441..4b1c2fcdd2 100644
--- a/Library/Homebrew/caveats.rb
+++ b/Library/Homebrew/caveats.rb
@@ -9,7 +9,7 @@ class Caveats
     caveats = []
     s = f.caveats.to_s
     caveats << s.chomp + "\n" if s.length > 0
-    caveats << f.keg_only_text if f.keg_only? && f.respond_to?(:keg_only_text)
+    caveats << keg_only_text
     caveats << bash_completion_caveats
     caveats << zsh_completion_caveats
     caveats << fish_completion_caveats
@@ -31,6 +31,27 @@ class Caveats
     end.compact.first
   end
 
+  def keg_only_text
+    return "" unless f.keg_only?
+
+    s = "This formula is keg-only, which means it was not symlinked into #{HOMEBREW_PREFIX}."
+    s << "\n\n#{f.keg_only_reason.to_s}"
+    if f.lib.directory? or f.include.directory?
+      s <<
+        <<-EOS.undent_________________________________________________________72
+
+
+        Generally there are no consequences of this for you. If you build your
+        own software and it requires this formula, you'll need to add to your
+        build variables:
+
+        EOS
+      s << "    LDFLAGS:  -L#{f.opt_lib}\n" if f.lib.directory?
+      s << "    CPPFLAGS: -I#{f.opt_include}\n" if f.include.directory?
+    end
+    s << "\n"
+  end
+
   def bash_completion_caveats
     if keg and keg.completion_installed? :bash then <<-EOS.undent
       Bash completion has been installed to:
diff --git a/Library/Homebrew/formula_installer.rb b/Library/Homebrew/formula_installer.rb
index 13a0cfc2be..52bf3a0a3b 100644
--- a/Library/Homebrew/formula_installer.rb
+++ b/Library/Homebrew/formula_installer.rb
@@ -676,25 +676,3 @@ class FormulaInstaller
     end
   end
 end
-
-
-class Formula
-  def keg_only_text
-    s = "This formula is keg-only, which means it was not symlinked into #{HOMEBREW_PREFIX}."
-    s << "\n\n#{keg_only_reason.to_s}"
-    if lib.directory? or include.directory?
-      s <<
-        <<-EOS.undent_________________________________________________________72
-
-
-        Generally there are no consequences of this for you. If you build your
-        own software and it requires this formula, you'll need to add to your
-        build variables:
-
-        EOS
-      s << "    LDFLAGS:  -L#{opt_lib}\n" if lib.directory?
-      s << "    CPPFLAGS: -I#{opt_include}\n" if include.directory?
-    end
-    s << "\n"
-  end
-end