Index: src/OFMutableTarArchiveEntry.h
==================================================================
--- src/OFMutableTarArchiveEntry.h
+++ src/OFMutableTarArchiveEntry.h
@@ -30,21 +30,21 @@
 }
 
 /**
  * @brief The mode of the entry.
  */
-@property (readwrite, nonatomic) unsigned long mode;
+@property (readwrite, retain, nonatomic) OFNumber *mode;
 
 /**
  * @brief The UID of the owner.
  */
-@property (readwrite, nonatomic) unsigned long UID;
+@property (readwrite, retain, nonatomic) OFNumber *UID;
 
 /**
  * @brief The GID of the group.
  */
-@property (readwrite, nonatomic) unsigned long GID;
+@property (readwrite, retain, nonatomic) OFNumber *GID;
 
 /**
  * @brief The date of the last modification of the file.
  */
 @property (readwrite, retain, nonatomic) OFDate *modificationDate;

Index: src/OFMutableTarArchiveEntry.m
==================================================================
--- src/OFMutableTarArchiveEntry.m
+++ src/OFMutableTarArchiveEntry.m
@@ -15,12 +15,13 @@
 
 #include "config.h"
 
 #import "OFMutableTarArchiveEntry.h"
 #import "OFTarArchiveEntry+Private.h"
-#import "OFString.h"
 #import "OFDate.h"
+#import "OFNumber.h"
+#import "OFString.h"
 
 @implementation OFMutableTarArchiveEntry
 @dynamic fileName, mode, UID, GID, compressedSize, uncompressedSize;
 @dynamic modificationDate, type, targetFileName, owner, group, deviceMajor;
 @dynamic deviceMinor;
@@ -58,23 +59,29 @@
 	OFString *old = _fileName;
 	_fileName = [fileName copy];
 	[old release];
 }
 
-- (void)setMode: (unsigned long)mode
+- (void)setMode: (OFNumber *)mode
 {
-	_mode = mode;
+	OFNumber *old = _mode;
+	_mode = [mode retain];
+	[old release];
 }
 
-- (void)setUID: (unsigned long)UID
+- (void)setUID: (OFNumber *)UID
 {
-	_UID = UID;
+	OFNumber *old = _UID;
+	_UID = [UID retain];
+	[old release];
 }
 
-- (void)setGID: (unsigned long)GID
+- (void)setGID: (OFNumber *)GID
 {
-	_GID = GID;
+	OFNumber *old = _GID;
+	_GID = [GID retain];
+	[old release];
 }
 
 - (void)setCompressedSize: (unsigned long long)compressedSize
 {
 	_compressedSize = compressedSize;

Index: src/OFTarArchiveEntry.h
==================================================================
--- src/OFTarArchiveEntry.h
+++ src/OFTarArchiveEntry.h
@@ -19,10 +19,11 @@
 OF_ASSUME_NONNULL_BEGIN
 
 /** @file */
 
 @class OFDate;
+@class OFNumber;
 
 /**
  * @brief The type of the archive entry.
  */
 typedef enum {
@@ -51,13 +52,12 @@
  */
 @interface OFTarArchiveEntry: OFObject <OFArchiveEntry, OFCopying,
     OFMutableCopying>
 {
 	OFString *_fileName;
-	unsigned long _mode;
+	OFNumber *_mode, *_UID, *_GID;
 	unsigned long long _compressedSize, _uncompressedSize;
-	unsigned long _UID, _GID;
 	OFDate *_modificationDate;
 	OFTarArchiveEntryType _type;
 	OFString *_Nullable _targetFileName;
 	OFString *_Nullable _owner, *_Nullable _group;
 	unsigned long _deviceMajor, _deviceMinor;
@@ -65,21 +65,21 @@
 }
 
 /**
  * @brief The mode of the entry.
  */
-@property (readonly, nonatomic) unsigned long mode;
+@property (readonly, retain, nonatomic) OFNumber *mode;
 
 /**
  * @brief The UID of the owner.
  */
-@property (readonly, nonatomic) unsigned long UID;
+@property (readonly, retain, nonatomic) OFNumber *UID;
 
 /**
  * @brief The GID of the group.
  */
-@property (readonly, nonatomic) unsigned long GID;
+@property (readonly, retain, nonatomic) OFNumber *GID;
 
 /**
  * @brief The date of the last modification of the file.
  */
 @property (readonly, retain, nonatomic) OFDate *modificationDate;

Index: src/OFTarArchiveEntry.m
==================================================================
--- src/OFTarArchiveEntry.m
+++ src/OFTarArchiveEntry.m
@@ -16,10 +16,11 @@
 #include "config.h"
 
 #import "OFTarArchiveEntry.h"
 #import "OFTarArchiveEntry+Private.h"
 #import "OFDate.h"
+#import "OFNumber.h"
 #import "OFStream.h"
 #import "OFString.h"
 
 #import "OFOutOfRangeException.h"
 
@@ -81,12 +82,17 @@
 
 - (instancetype)of_init
 {
 	self = [super init];
 
-	_type = OFTarArchiveEntryTypeFile;
-	_mode = 0644;
+	@try {
+		_type = OFTarArchiveEntryTypeFile;
+		_mode = [[OFNumber alloc] initWithUnsignedShort: 0644];
+	} @catch (id e) {
+		[self release];
+		@throw e;
+	}
 
 	return self;
 }
 
 - (instancetype)of_initWithHeader: (unsigned char [512])header
@@ -97,16 +103,16 @@
 	@try {
 		void *pool = objc_autoreleasePoolPush();
 		OFString *targetFileName;
 
 		_fileName = [stringFromBuffer(header, 100, encoding) copy];
-		_mode = (unsigned long)octalValueFromBuffer(
-		    header + 100, 8, ULONG_MAX);
-		_UID = (unsigned long)octalValueFromBuffer(
-		    header + 108, 8, ULONG_MAX);
-		_GID = (unsigned long)octalValueFromBuffer(
-		    header + 116, 8, ULONG_MAX);
+		_mode = [[OFNumber alloc] initWithUnsignedLongLong:
+		    octalValueFromBuffer(header + 100, 8, ULONG_MAX)];
+		_UID = [[OFNumber alloc] initWithUnsignedLongLong:
+		    octalValueFromBuffer(header + 108, 8, ULONG_MAX)];
+		_GID = [[OFNumber alloc] initWithUnsignedLongLong:
+		    octalValueFromBuffer(header + 116, 8, ULONG_MAX)];
 		_uncompressedSize = (unsigned long long)octalValueFromBuffer(
 		    header + 124, 12, ULLONG_MAX);
 		_compressedSize =
 		    _uncompressedSize + (512 - _uncompressedSize % 512);
 		_modificationDate = [[OFDate alloc]
@@ -155,10 +161,13 @@
 }
 
 - (void)dealloc
 {
 	[_fileName release];
+	[_mode release];
+	[_UID release];
+	[_GID release];
 	[_modificationDate release];
 	[_targetFileName release];
 	[_owner release];
 	[_group release];
 
@@ -197,21 +206,21 @@
 - (OFString *)fileName
 {
 	return _fileName;
 }
 
-- (unsigned long)mode
+- (OFNumber *)mode
 {
 	return _mode;
 }
 
-- (unsigned long)UID
+- (OFNumber *)UID
 {
 	return _UID;
 }
 
-- (unsigned long)GID
+- (OFNumber *)GID
 {
 	return _GID;
 }
 
 - (unsigned long long)compressedSize

Index: utils/ofarc/TarArchive.m
==================================================================
--- utils/ofarc/TarArchive.m
+++ utils/ofarc/TarArchive.m
@@ -31,11 +31,12 @@
 
 static void
 setPermissions(OFString *path, OFTarArchiveEntry *entry)
 {
 #ifdef OF_FILE_MANAGER_SUPPORTS_PERMISSIONS
-	OFNumber *mode = [OFNumber numberWithUnsignedShort: entry.mode & 0777];
+	OFNumber *mode = [OFNumber numberWithUnsignedLongLong:
+	    entry.mode.longLongValue & 0777];
 	OFFileAttributes attributes = [OFDictionary
 	    dictionaryWithObject: mode
 			  forKey: OFFilePOSIXPermissions];
 
 	[[OFFileManager defaultManager] setAttributes: attributes
@@ -115,15 +116,13 @@
 			OFString *date = [entry.modificationDate
 			    localDateStringWithFormat: @"%Y-%m-%d %H:%M:%S"];
 			OFString *size = [OFString stringWithFormat:
 			    @"%llu", entry.uncompressedSize];
 			OFString *mode = [OFString stringWithFormat:
-			    @"%06o", entry.mode];
-			OFString *UID = [OFString stringWithFormat:
-			    @"%u", entry.UID];
-			OFString *GID = [OFString stringWithFormat:
-			    @"%u", entry.GID];
+			    @"%06llo", entry.mode.unsignedLongLongValue];
+			OFString *UID = entry.UID.description;
+			OFString *GID = entry.GID.description;
 
 			[OFStdOut writeString: @"\t"];
 			[OFStdOut writeLine: OF_LOCALIZED(@"list_size",
 			    @"["
 			    @"    'Size: ',"
@@ -477,18 +476,19 @@
 		attributes = [fileManager attributesOfItemAtPath: fileName];
 		type = attributes.fileType;
 		entry = [OFMutableTarArchiveEntry entryWithFileName: fileName];
 
 #ifdef OF_FILE_MANAGER_SUPPORTS_PERMISSIONS
-		entry.mode = attributes.filePOSIXPermissions;
+		entry.mode = [attributes objectForKey: OFFilePOSIXPermissions];
 #endif
 		entry.uncompressedSize = attributes.fileSize;
 		entry.modificationDate = attributes.fileModificationDate;
 
 #ifdef OF_FILE_MANAGER_SUPPORTS_OWNER
-		entry.UID = attributes.fileOwnerAccountID;
-		entry.GID = attributes.fileGroupOwnerAccountID;
+		entry.UID = [attributes objectForKey: OFFileOwnerAccountID];
+		entry.GID =
+		    [attributes objectForKey: OFFileGroupOwnerAccountID];
 		entry.owner = attributes.fileOwnerAccountName;
 		entry.group = attributes.fileGroupOwnerAccountName;
 #endif
 
 		if ([type isEqual: OFFileTypeRegular])