diff --git a/libvncserver/main.c b/libvncserver/main.c
index 6cf21ea..a46b3bc 100644
--- a/libvncserver/main.c
+++ b/libvncserver/main.c
@@ -194,7 +194,7 @@ rfbBool rfbDisableExtension(rfbClientPtr cl, rfbProtocolExtension* extension)
 	return FALSE;
 }
 
-void* rfbGetExtensionClientData(rfbClientPtr cl, rfbExtensionData* extension)
+void* rfbGetExtensionClientData(rfbClientPtr cl, rfbProtocolExtension* extension)
 {
     rfbExtensionData* data = cl->extensions;
 
diff --git a/rfb/rfb.h b/rfb/rfb.h
index 4eb4cb1..aee6b45 100644
--- a/rfb/rfb.h
+++ b/rfb/rfb.h
@@ -799,7 +799,7 @@ void rfbReleaseExtensionIterator();
 rfbBool rfbEnableExtension(rfbClientPtr cl, rfbProtocolExtension* extension,
 	void* data);
 rfbBool rfbDisableExtension(rfbClientPtr cl, rfbProtocolExtension* extension);
-void* rfbGetExtensionClientData(rfbClientPtr cl, rfbExtensionData* extension);
+void* rfbGetExtensionClientData(rfbClientPtr cl, rfbProtocolExtension* extension);
 
 /* to check against plain passwords */
 rfbBool rfbCheckPasswordByList(rfbClientPtr cl,const char* response,int len);