diff --git a/lib/roken/hstrerror.c b/lib/roken/hstrerror.c
index 9b5f49637..666fc92fd 100644
--- a/lib/roken/hstrerror.c
+++ b/lib/roken/hstrerror.c
@@ -9,7 +9,9 @@
 #include <stdio.h>
 #include <netdb.h>
 
-static char *msg[] = {
+static
+const
+char *const msg[] = {
   "No error",
   "Authoritative Answer Host not found",
   "Non-Authoritive Host not found, or SERVERFAIL",
@@ -17,9 +19,10 @@ static char *msg[] = {
   "Valid name, no data record of requested type"
 };
 
+const
 char *hstrerror(int herr)
 {
-  if(herr >= 0 && herr <= 4)
+  if (herr >= 0 && herr <= 4)
     return msg[herr];
   return "Error number out of range (hstrerror)";
 }
diff --git a/lib/roken/roken.h b/lib/roken/roken.h
index 0d69ce329..d56a90080 100644
--- a/lib/roken/roken.h
+++ b/lib/roken/roken.h
@@ -42,7 +42,7 @@ char *strerror(int eno);
 #endif
 
 #ifndef HAVE_HSTRERROR
-char *hstrerror(int herr);
+const char *hstrerror(int herr);
 #endif
 
 #ifndef HAVE_HERROR
diff --git a/lib/roken/roken.h.in b/lib/roken/roken.h.in
index 0d69ce329..d56a90080 100644
--- a/lib/roken/roken.h.in
+++ b/lib/roken/roken.h.in
@@ -42,7 +42,7 @@ char *strerror(int eno);
 #endif
 
 #ifndef HAVE_HSTRERROR
-char *hstrerror(int herr);
+const char *hstrerror(int herr);
 #endif
 
 #ifndef HAVE_HERROR