diff --git a/src/ops.c b/src/ops.c
index 6df1121..a4261cb 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -856,11 +856,12 @@
     if (       (regname > 0 && ASCII_ISALNUM(regname))
 	    || (!writing && vim_strchr((char_u *)
 #ifdef FEAT_EVAL
-				    "/.%#:="
+				    "/.%:="
 #else
-				    "/.%#:"
+				    "/.%:"
 #endif
 					, regname) != NULL)
+	    || regname == '#'
 	    || regname == '"'
 	    || regname == '-'
 	    || regname == '_'
@@ -6514,6 +6515,27 @@
 	return;
     }
 
+    if (name == '#')
+    {
+	buf_T	*buf;
+
+	if (VIM_ISDIGIT(*str))
+	{
+	    int	num = atoi((char *)str);
+
+	    buf = buflist_findnr(num);
+	    if (buf == NULL)
+		EMSGN(_(e_nobufnr), (long)num);
+	}
+	else
+	    buf = buflist_findnr(buflist_findpat(str, str + STRLEN(str),
+							 TRUE, FALSE, FALSE));
+	if (buf == NULL)
+	    return;
+	curwin->w_alt_fnum = buf->b_fnum;
+	return;
+    }
+
 #ifdef FEAT_EVAL
     if (name == '=')
     {