diff --git a/src/network/net_message.cpp b/src/network/net_message.cpp
index edfa0c1ab..b78b289c1 100644
--- a/src/network/net_message.cpp
+++ b/src/network/net_message.cpp
@@ -728,7 +728,7 @@ size_t CNetworkPacketHeader::Deserialize(const unsigned char *buf)
 // CNetworkPacket
 //
 
-unsigned CNetworkPacket::Serialize(unsigned char *buf, int numcommands) const
+size_t CNetworkPacket::Serialize(unsigned char *buf, int numcommands) const
 {
 	unsigned char *p = buf;