gistfile1.txt

[] ~/projects/jruby $ jruby -e 'p 2147483648.times.count'
2147483648

[] ~/projects/jruby $ git diff
diff --git a/core/src/main/java/org/jruby/RubyEnumerable.java b/core/src/main/java/org/jruby/RubyEnumerable.java
index 80979c8088..66a48cfa95 100644
--- a/core/src/main/java/org/jruby/RubyEnumerable.java
+++ b/core/src/main/java/org/jruby/RubyEnumerable.java
@@ -160,7 +160,7 @@ public class RubyEnumerable {
 
     private static IRubyObject countCommon(ThreadContext context, IRubyObject self, final Block block) {
         final Ruby runtime = context.runtime;
-        final int result[] = new int[] { 0 };
+        final long result[] = new long[] { 0 };
 
         if (block.isGiven()) {
             each(context, self, new JavaInternalBlockBody(runtime, context, "Enumerable#count", block.getSignature()) {