diff --git a/sifflet.cabal b/sifflet.cabal
--- a/sifflet.cabal
+++ b/sifflet.cabal
@@ -1,5 +1,5 @@
 name: sifflet
-version: 1.2
+version: 1.2.1
 cabal-version: >= 1.8
 build-type: Simple
 license: BSD3
@@ -17,6 +17,7 @@
   Sifflet show the intermediate steps of the computation
   on the diagram, and can expand function calls to show further details.
   It is intended as an aid for learning about recursion.
+  Version 1.2.1: updated for compatibility with gtk-0.12.
 category: 
   Language 
   , Visual Programming
@@ -37,9 +38,9 @@
   build-depends: 
     base >= 4.0 && < 4.3,
     -- begin GTK stuff, no longer needing exactly the same version numbers
-    cairo == 0.11.*,
-    glib == 0.11.*,
-    gtk == 0.11.*,
+    cairo >= 0.11 && < 0.13,
+    glib >= 0.11 && < 0.13,
+    gtk >= 0.11 && < 0.13,
     -- end
     containers >= 0.2 && < 0.4,
     fgl >= 5.4 && < 5.5,
@@ -47,7 +48,7 @@
     hxt >= 9 && < 9.1,
     mtl >= 1.1 && < 1.2,
     process >= 1.0 && < 1.1,
-    sifflet-lib >= 1.2
+    sifflet-lib >= 1.2.1
 
   if !os(windows)
     build-depends: unix >= 2.3 && < 2.5