diff --git a/src/sbbs3/userdat.c b/src/sbbs3/userdat.c
index 4a8e8d2ae0b5f8400751441b12dd8f6a53ffb85d..9c3d9abc5572a3af11eb2b4896a4c697eb92a9f9 100644
--- a/src/sbbs3/userdat.c
+++ b/src/sbbs3/userdat.c
@@ -38,7 +38,7 @@
 #include "sbbs.h"
 #include "cmdshell.h"
 #ifndef USHRT_MAX
-	#define USHRT_MAX ((1<<sizeof(unsigned short))-1)
+	#define USHRT_MAX ((unsigned short)~0)
 #endif
 
 /* convenient space-saving global variables */