diff --git a/java/src/com/android/inputmethod/keyboard/MoreKeysKeyboard.java b/java/src/com/android/inputmethod/keyboard/MoreKeysKeyboard.java
index 66c3014..f81ab8d 100644
--- a/java/src/com/android/inputmethod/keyboard/MoreKeysKeyboard.java
+++ b/java/src/com/android/inputmethod/keyboard/MoreKeysKeyboard.java
@@ -73,10 +73,11 @@
                 final int rowHeight, final int coordXInParent, final int parentKeyboardWidth,
                 final boolean isFixedColumnOrder, final int dividerWidth) {
             mIsFixedOrder = isFixedColumnOrder;
-            if (parentKeyboardWidth / keyWidth < maxColumns) {
+            if (parentKeyboardWidth / keyWidth < Math.min(numKeys, maxColumns)) {
                 throw new IllegalArgumentException(
                         "Keyboard is too small to hold more keys keyboard: "
-                                + parentKeyboardWidth + " " + keyWidth + " " + maxColumns);
+                                + parentKeyboardWidth + " " + keyWidth + " "
+                                + numKeys + " " + maxColumns);
             }
             mDefaultKeyWidth = keyWidth;
             mDefaultRowHeight = rowHeight;
diff --git a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
index e7c7e2b..17d2815 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FusionDictionary.java
@@ -647,7 +647,7 @@
 
         if (index < codePoints.length) return null;
         if (!currentGroup.isTerminal()) return null;
-        if (DBG && !codePoints.equals(checker.toString())) return null;
+        if (DBG && !string.equals(checker.toString())) return null;
         return currentGroup;
     }
 
@@ -853,16 +853,19 @@
                 if (currentPos.pos.hasNext()) {
                     final CharGroup currentGroup = currentPos.pos.next();
                     currentPos.length = mCurrentString.length();
-                    for (int i : currentGroup.mChars)
+                    for (int i : currentGroup.mChars) {
                         mCurrentString.append(Character.toChars(i));
+                    }
                     if (null != currentGroup.mChildren) {
                         currentPos = new Position(currentGroup.mChildren.mData);
+                        currentPos.length = mCurrentString.length();
                         mPositions.addLast(currentPos);
                     }
-                    if (currentGroup.mFrequency >= 0)
+                    if (currentGroup.mFrequency >= 0) {
                         return new Word(mCurrentString.toString(), currentGroup.mFrequency,
                                 currentGroup.mShortcutTargets, currentGroup.mBigrams,
                                 currentGroup.mIsNotAWord, currentGroup.mIsBlacklistEntry);
+                    }
                 } else {
                     mPositions.removeLast();
                     currentPos = mPositions.getLast();
diff --git a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
index 2c18b6e..0c480ea 100644
--- a/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
+++ b/java/src/com/android/inputmethod/latin/spellcheck/SpellCheckerProximityInfo.java
@@ -16,11 +16,10 @@
 
 package com.android.inputmethod.latin.spellcheck;
 
-import com.android.inputmethod.keyboard.ProximityInfo;
-import com.android.inputmethod.latin.CollectionUtils;
-import com.android.inputmethod.latin.Constants;
+import android.util.SparseIntArray;
 
-import java.util.TreeMap;
+import com.android.inputmethod.keyboard.ProximityInfo;
+import com.android.inputmethod.latin.Constants;
 
 public final class SpellCheckerProximityInfo extends ProximityInfo {
     public SpellCheckerProximityInfo(final int script) {
@@ -43,29 +42,14 @@
     public static final int NOT_A_COORDINATE_PAIR = -1;
 
     // Helper methods
-    static void buildProximityIndices(final int[] proximity,
-            final TreeMap<Integer, Integer> indices) {
-        for (int i = 0; i < proximity.length; i += ROW_SIZE) {
-            if (NUL != proximity[i]) indices.put(proximity[i], i / ROW_SIZE);
+    static void buildProximityIndices(final int[] proximity, final int rowSize,
+            final SparseIntArray indices) {
+        for (int i = 0; i < proximity.length; i += rowSize) {
+            if (NUL != proximity[i]) indices.put(proximity[i], i / rowSize);
         }
     }
 
-    static int computeIndex(final int characterCode,
-            final TreeMap<Integer, Integer> indices) {
-        final Integer result = indices.get(characterCode);
-        if (null == result) return NOT_AN_INDEX;
-        return result;
-    }
-
     private static final class Latin {
-        // This is a map from the code point to the index in the PROXIMITY array.
-        // At the time the native code to read the binary dictionary needs the proximity info be
-        // passed as a flat array spaced by MAX_PROXIMITY_CHARS_SIZE columns, one for each input
-        // character.
-        // Since we need to build such an array, we want to be able to search in our big proximity
-        // data quickly by character, and a map is probably the best way to do this.
-        private static final TreeMap<Integer, Integer> INDICES = CollectionUtils.newTreeMap();
-
         // The proximity here is the union of
         // - the proximity for a QWERTY keyboard.
         // - the proximity for an AZERTY keyboard.
@@ -125,17 +109,20 @@
             NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
         };
 
-        static {
-            buildProximityIndices(PROXIMITY, INDICES);
-        }
+        // This is a mapping array from the code point to the index in the PROXIMITY array.
+        // When we check the spelling of a word, we need to pass (x,y) coordinates to the native
+        // code for each letter of the word. These are most easily computed from the index in the
+        // PROXIMITY array. Since we'll need to do that very often, the index lookup from the code
+        // point needs to be as fast as possible, and a map is probably the best way to do this.
+        // To avoid unnecessary boxing conversion to Integer, here we use SparseIntArray.
+        static final SparseIntArray INDICES = new SparseIntArray(PROXIMITY.length / ROW_SIZE);
 
-        static int getIndexOf(int characterCode) {
-            return computeIndex(characterCode, INDICES);
+        static {
+            buildProximityIndices(PROXIMITY, ROW_SIZE, INDICES);
         }
     }
 
     private static final class Cyrillic {
-        private static final TreeMap<Integer, Integer> INDICES = CollectionUtils.newTreeMap();
         // TODO: The following table is solely based on the keyboard layout. Consult with Russian
         // speakers on commonly misspelled words/letters.
         /*
@@ -286,17 +273,14 @@
             NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
         };
 
-        static {
-            buildProximityIndices(PROXIMITY, INDICES);
-        }
+        static final SparseIntArray INDICES = new SparseIntArray(PROXIMITY.length / ROW_SIZE);
 
-        static int getIndexOf(int characterCode) {
-            return computeIndex(characterCode, INDICES);
+        static {
+            buildProximityIndices(PROXIMITY, ROW_SIZE, INDICES);
         }
     }
 
     private static final class Greek {
-        private static final TreeMap<Integer, Integer> INDICES = CollectionUtils.newTreeMap();
         // TODO: The following table is solely based on the keyboard layout. Consult with Greek
         // speakers on commonly misspelled words/letters.
         /*
@@ -427,12 +411,10 @@
             NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
         };
 
-        static {
-            buildProximityIndices(PROXIMITY, INDICES);
-        }
+        static final SparseIntArray INDICES = new SparseIntArray(PROXIMITY.length / ROW_SIZE);
 
-        static int getIndexOf(int characterCode) {
-            return computeIndex(characterCode, INDICES);
+        static {
+            buildProximityIndices(PROXIMITY, ROW_SIZE, INDICES);
         }
     }
 
@@ -452,11 +434,11 @@
     private static int getIndexOfCodeForScript(final int codePoint, final int script) {
         switch (script) {
         case AndroidSpellCheckerService.SCRIPT_LATIN:
-            return Latin.getIndexOf(codePoint);
+            return Latin.INDICES.get(codePoint, NOT_AN_INDEX);
         case AndroidSpellCheckerService.SCRIPT_CYRILLIC:
-            return Cyrillic.getIndexOf(codePoint);
+            return Cyrillic.INDICES.get(codePoint, NOT_AN_INDEX);
         case AndroidSpellCheckerService.SCRIPT_GREEK:
-            return Greek.getIndexOf(codePoint);
+            return Greek.INDICES.get(codePoint, NOT_AN_INDEX);
         default:
             throw new RuntimeException("Wrong script supplied: " + script);
         }