--- a/configure.in
+++ b/configure.in
@@ -9054,19 +9054,25 @@ dnl ICU Support
 dnl ========================================================
 
 # Internationalization isn't built or exposed by default in non-desktop
 # builds.  Bugs to enable:
 #
 #   Android:  bug 864843
 #   B2G:      bug 866301
 
-if test "$MOZ_WIDGET_TOOLKIT" = "android" ||
-   test "$MOZ_BUILD_APP" = "b2g"; then
+if test "$MOZ_WIDGET_TOOLKIT" = "android"; then
     _INTL_API=no
+elif test "$MOZ_BUILD_APP" = "b2g"; then
+    if test "$MOZ_WIDGET_TOOLKIT" = "cocoa"; then
+        # nsCollationMacUC needs ICU
+        _INTL_API=yes
+    else
+        _INTL_API=no
+    fi
 else
     _INTL_API=yes
 fi
 
 MOZ_CONFIG_ICU()
 
 if test -z "$JS_SHARED_LIBRARY"; then
   AC_DEFINE(MOZ_STATIC_JS)