Index: src/bridge/NSArray_OFArray.m
==================================================================
--- src/bridge/NSArray_OFArray.m
+++ src/bridge/NSArray_OFArray.m
@@ -16,10 +16,12 @@
 
 #import "NSArray_OFArray.h"
 #import "OFArray.h"
 #import "OFBridging.h"
 
+#import "OFOutOfRangeException.h"
+
 @implementation NSArray_OFArray
 - initWithOFArray: (OFArray*)array_
 {
 	if ((self = [super init]) != nil) {
 		@try {
@@ -30,20 +32,25 @@
 	}
 
 	return self;
 }
 
-- (id)objectAtIndex: (size_t)index
+- (id)objectAtIndex: (NSUInteger)index
 {
 	id object = [array objectAtIndex: index];
 
 	if ([object conformsToProtocol: @protocol(OFBridging)])
 		return [object NSObject];
 
 	return object;
 }
 
-- (size_t)count
+- (NSUInteger)count
 {
-	return [array count];
+	size_t count = [array count];
+
+	if (count > NSUIntegerMax)
+		@throw [OFOutOfRangeException exceptionWithClass: [self class]];
+
+	return (NSUInteger)count;
 }
 @end

Index: src/bridge/NSDictionary_OFDictionary.m
==================================================================
--- src/bridge/NSDictionary_OFDictionary.m
+++ src/bridge/NSDictionary_OFDictionary.m
@@ -17,10 +17,12 @@
 #import "NSDictionary_OFDictionary.h"
 #import "OFDictionary.h"
 
 #import "NSBridging.h"
 #import "OFBridging.h"
+
+#import "OFOutOfRangeException.h"
 
 @implementation NSDictionary_OFDictionary
 - initWithOFDictionary: (OFDictionary*)dictionary_
 {
 	if ((self = [super init]) != nil) {
@@ -47,10 +49,15 @@
 		return [object NSObject];
 
 	return object;
 }
 
-- (size_t)count
+- (NSUInteger)count
 {
-	return [dictionary count];
+	size_t count = [dictionary count];
+
+	if (count > NSUIntegerMax)
+		@throw [OFOutOfRangeException exceptionWithClass: [self class]];
+
+	return (NSUInteger)count;
 }
 @end

Index: src/bridge/OFArray_NSArray.m
==================================================================
--- src/bridge/OFArray_NSArray.m
+++ src/bridge/OFArray_NSArray.m
@@ -18,10 +18,11 @@
 
 #import "OFArray_NSArray.h"
 #import "NSBridging.h"
 
 #import "OFInitializationFailedException.h"
+#import "OFOutOfRangeException.h"
 
 @implementation OFArray_NSArray
 - initWithNSArray: (NSArray*)array_
 {
 	self = [super init];
@@ -40,11 +41,16 @@
 	return self;
 }
 
 - (id)objectAtIndex: (size_t)index
 {
-	id object = [array objectAtIndex: index];
+	id object;
+
+	if (index > NSUIntegerMax)
+		@throw [OFOutOfRangeException exceptionWithClass: [self class]];
+
+	object = [array objectAtIndex: index];
 
 	if ([object conformsToProtocol: @protocol(NSBridging)])
 		return [object OFObject];
 
 	return object;