3 files changed, 7 insertions, 4 deletions
diff --git a/src/modules/m_spanningtree/capab.cpp b/src/modules/m_spanningtree/capab.cpp
index 18f25b2c6..ef0e16d2d 100644
--- a/src/modules/m_spanningtree/capab.cpp
+++ b/src/modules/m_spanningtree/capab.cpp
@@ -238,7 +238,7 @@ bool TreeSocket::Capab(const CommandBase::Params& params)
 		capab->OptModuleList.clear();
 		capab->CapKeys.clear();
 		if (params.size() > 1)
-			proto_version = ConvToNum<unsigned int>(params[1]);
+			proto_version = ConvToNum<uint16_t>(params[1]);
 
 		if (proto_version < PROTO_OLDEST)
 		{
diff --git a/src/modules/m_spanningtree/main.h b/src/modules/m_spanningtree/main.h
index aa8623e0f..9a582bf49 100644
--- a/src/modules/m_spanningtree/main.h
+++ b/src/modules/m_spanningtree/main.h
@@ -45,16 +45,19 @@
  * If you introduce new protocol versions please document them here:
  * https://docs.inspircd.org/spanningtree/changes
  */
-enum ProtocolVersion
+enum ProtocolVersion : uint16_t
 {
 	/** The linking protocol version introduced in InspIRCd v3.0. */
 	PROTO_INSPIRCD_30 = 1205,
 
+	/** The linking protocol version introduced in InspIRCd v4.0a1. */
+	PROTO_INSPIRCD_40_A1 = 1206,
+
 	/** The oldest version of the protocol that we support. */
 	PROTO_OLDEST = PROTO_INSPIRCD_30,
 
 	/** The newest version of the protocol that we support. */
-	PROTO_NEWEST = PROTO_INSPIRCD_30
+	PROTO_NEWEST = PROTO_INSPIRCD_40_A1
 };
 
 /** Forward declarations
diff --git a/src/modules/m_spanningtree/treesocket.h b/src/modules/m_spanningtree/treesocket.h
index 925afac2e..bc08183af 100644
--- a/src/modules/m_spanningtree/treesocket.h
+++ b/src/modules/m_spanningtree/treesocket.h
@@ -112,7 +112,7 @@ class TreeSocket : public BufferedSocket
 	TreeServer* MyRoot = NULL;
 
 	/* Remote protocol version */
-	unsigned int proto_version = 0;
+	uint16_t proto_version = 0;
 
 	/** Checks if the given servername and sid are both free
 	 */