diff --git a/bin/mkpeep.pike b/bin/mkpeep.pike
index da13252d343db38bf1fa476147e95b33fd570e1a..785eded50b25f5428e41302f76afb9b11ce45da8 100755
--- a/bin/mkpeep.pike
+++ b/bin/mkpeep.pike
@@ -367,7 +367,7 @@ class Breakable {
     foreach(lines, string|array(string) line)
       if(stringp(line)) {
 	if(String.trim_all_whites([string]line)=="")
-	  ret += line;
+	  ret += [string]line;
 	else
 	  ret += sprintf("%*n%s\n", ind, [string]line);
       }