diff --git a/lib/roken/roken.h b/lib/roken/roken.h
index fcc343bbb..cd2a1333a 100644
--- a/lib/roken/roken.h
+++ b/lib/roken/roken.h
@@ -14,6 +14,10 @@ int putenv(const char *string);
 int setenv(const char *var, const char *val, int rewrite);
 #endif
 
+#ifndef HAVE_UNSETENV
+void unsetenv(const char *name);
+#endif
+
 #ifndef HAVE_GETUSERSHELL
 char *getusershell(void);
 #endif
@@ -43,6 +47,10 @@ char *strerror(int eno);
 char *hstrerror(int herr);
 #endif
 
+#ifndef HAVE_HERROR
+void herror(char *s);
+#endif
+
 #ifndef HAVE_INET_ATON
 /* Minimal implementation of inet_aton. Doesn't handle hex numbers. */
 #ifndef __GNUC__
@@ -54,4 +62,12 @@ int inet_aton(char *cp, struct in_addr *adr);
 char* getcwd(char *path, int size);
 #endif
 
+#ifndef HAVE_GETENT
+int getent(char *cp, char *name);
+#endif
+
+#ifndef HAVE_GETSTR
+char *getstr(char *id, char **cpp);
+#endif
+
 #endif /*  __ROKEN_H__ */
diff --git a/lib/roken/roken.h.in b/lib/roken/roken.h.in
index fcc343bbb..cd2a1333a 100644
--- a/lib/roken/roken.h.in
+++ b/lib/roken/roken.h.in
@@ -14,6 +14,10 @@ int putenv(const char *string);
 int setenv(const char *var, const char *val, int rewrite);
 #endif
 
+#ifndef HAVE_UNSETENV
+void unsetenv(const char *name);
+#endif
+
 #ifndef HAVE_GETUSERSHELL
 char *getusershell(void);
 #endif
@@ -43,6 +47,10 @@ char *strerror(int eno);
 char *hstrerror(int herr);
 #endif
 
+#ifndef HAVE_HERROR
+void herror(char *s);
+#endif
+
 #ifndef HAVE_INET_ATON
 /* Minimal implementation of inet_aton. Doesn't handle hex numbers. */
 #ifndef __GNUC__
@@ -54,4 +62,12 @@ int inet_aton(char *cp, struct in_addr *adr);
 char* getcwd(char *path, int size);
 #endif
 
+#ifndef HAVE_GETENT
+int getent(char *cp, char *name);
+#endif
+
+#ifndef HAVE_GETSTR
+char *getstr(char *id, char **cpp);
+#endif
+
 #endif /*  __ROKEN_H__ */
diff --git a/lib/roken/unsetenv.c b/lib/roken/unsetenv.c
index bcf7966e5..685aefc72 100644
--- a/lib/roken/unsetenv.c
+++ b/lib/roken/unsetenv.c
@@ -2,10 +2,13 @@
 #include <config.h>
 #endif
 
-#include <stdlib.h>
-
 RCSID("$Id$");
 
+#include <stdlib.h>
+#include <string.h>
+
+#include "roken.h"
+
 extern char **environ;
 
 /*