diff --git a/MKNetworkKit/MKNetworkOperation.m b/MKNetworkKit/MKNetworkOperation.m
index daf0e9e..206e5ab 100644
--- a/MKNetworkKit/MKNetworkOperation.m
+++ b/MKNetworkKit/MKNetworkOperation.m
@@ -376,6 +376,8 @@ -(void) setState:(MKNetworkOperationState)newState {
 - (void)encodeWithCoder:(NSCoder *)encoder 
 {
   [encoder encodeInteger:self.stringEncoding forKey:@"stringEncoding"];
+  [encoder encodeInteger:_postDataEncoding forKey:@"postDataEncoding"];
+
   [encoder encodeObject:self.uniqueId forKey:@"uniqueId"];
   [encoder encodeObject:self.request forKey:@"request"];
   [encoder encodeObject:self.response forKey:@"response"];
@@ -401,6 +403,7 @@ - (id)initWithCoder:(NSCoder *)decoder
   self = [super init];
   if (self) {
     [self setStringEncoding:[decoder decodeIntegerForKey:@"stringEncoding"]];
+    _postDataEncoding = [decoder decodeIntegerForKey:@"postDataEncoding"];
     self.request = [decoder decodeObjectForKey:@"request"];
     self.uniqueId = [decoder decodeObjectForKey:@"uniqueId"];
     
@@ -426,6 +429,7 @@ - (id)copyWithZone:(NSZone *)zone
 {
   MKNetworkOperation *theCopy = [[[self class] allocWithZone:zone] init];  // use designated initializer
   
+  theCopy.postDataEncoding = _postDataEncoding;
   [theCopy setStringEncoding:self.stringEncoding];
   [theCopy setUniqueId:[self.uniqueId copy]];