diff --git a/bin/install.pike b/bin/install.pike
index 85d8dbaac6d4080bcf2fd15188a2db672d133358..da4fa7cc5ffba4ec8eb75409bd04b71f17268822 100644
--- a/bin/install.pike
+++ b/bin/install.pike
@@ -569,10 +569,10 @@ int main(int argc, string *argv)
   switch(install_type)
   {
     case "--traditional":
-      exec_prefix=vars->exec_prefix||prefix;
-      lib_prefix=vars->lib_prefix||prefix;
+      exec_prefix=vars->exec_prefix||prefix+="/bin/";
+      lib_prefix=vars->lib_prefix||prefix+="/lib/pike/";
       include_prefix=combine_path(prefix,"include","pike");
-      man_prefix=vars->man_prefix||prefix;
+      man_prefix=vars->man_prefix||prefix+="/man/;
       break;
 
     case "--interactive":