diff --git a/modules/aaa/mod_auth_ldap.c b/modules/aaa/mod_auth_ldap.c
index 0beeda8c89..c23cffcd9b 100644
--- a/modules/aaa/mod_auth_ldap.c
+++ b/modules/aaa/mod_auth_ldap.c
@@ -60,13 +60,14 @@
  * Copyright 1999-2001 Dave Carrigan
  */
 
-/* for getpid() */
-#include <unistd.h>
-
 #include <apr_ldap.h>
 #include <apr_strings.h>
 
 #include "ap_config.h"
+#if APR_HAVE_UNISTD_H
+/* for getpid() */
+#include <unistd.h>
+#endif
 #include "httpd.h"
 #include "http_config.h"
 #include "http_core.h"
diff --git a/modules/ldap/util_ldap.c b/modules/ldap/util_ldap.c
index 5f3387a6ba..433ea097e3 100644
--- a/modules/ldap/util_ldap.c
+++ b/modules/ldap/util_ldap.c
@@ -77,7 +77,9 @@
 #include "util_ldap.h"
 #include "util_ldap_cache.h"
 
+#if APR_HAVE_UNISTD_H
 #include <unistd.h>
+#endif
 
 module AP_MODULE_DECLARE_DATA ldap_module;
 
diff --git a/modules/ssl/mod_ssl.h b/modules/ssl/mod_ssl.h
index c3afa4e349..83b5d42afa 100644
--- a/modules/ssl/mod_ssl.h
+++ b/modules/ssl/mod_ssl.h
@@ -97,9 +97,6 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <time.h>
-#if APR_HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
 /* XXX: these better go away */
 #include <assert.h>
 
@@ -142,6 +139,16 @@
 #include "ssl_util_ssl.h"
 #include "ssl_util_table.h"
 
+/* The #ifdef macros are only defined AFTER including the above
+ * therefore we cannot include these system files at the top  :-(
+ */
+#if APR_HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#if APR_HAVE_UNISTD_H
+#include <unistd.h> /* needed for STDIN_FILENO et.al., at least on FreeBSD */
+#endif
+
 /*
  * Provide reasonable default for some defines
  */
diff --git a/modules/ssl/ssl_expr_scan.c b/modules/ssl/ssl_expr_scan.c
index a2f29924e3..ddfa2fd5a8 100644
--- a/modules/ssl/ssl_expr_scan.c
+++ b/modules/ssl/ssl_expr_scan.c
@@ -38,7 +38,6 @@
 #ifdef __cplusplus
 
 #include <stdlib.h>
-#include <unistd.h>
 
 /* Use prototypes in function declarations. */
 #define YY_USE_PROTOS
diff --git a/server/mpm/worker/fdqueue.h b/server/mpm/worker/fdqueue.h
index a253bbfb28..c59ea254eb 100644
--- a/server/mpm/worker/fdqueue.h
+++ b/server/mpm/worker/fdqueue.h
@@ -60,7 +60,9 @@
 #define FDQUEUE_H
 #include "httpd.h"
 #include <stdlib.h>
+#if APR_HAVE_UNISTD_H
 #include <unistd.h>
+#endif
 #include <pthread.h>
 #include <sys/types.h>
 #include <sys/socket.h>
diff --git a/support/suexec.c b/support/suexec.c
index 8550ba9abe..1d77833a89 100644
--- a/support/suexec.c
+++ b/support/suexec.c
@@ -74,7 +74,9 @@
 #include <sys/types.h>
 #include <string.h>
 #include <time.h>
+#if APR_HAVE_UNISTD_H
 #include <unistd.h>
+#endif
 
 #include <stdio.h>
 #include <stdarg.h>