diff -ru nginx-1.0.3/auto/unix nginx-1.0.3-posix-sem-rt/auto/unix
--- nginx-1.0.3/auto/unix	2011-05-10 06:39:13.000000000 -0500
+++ nginx-1.0.3-posix-sem-rt/auto/unix	2011-05-26 19:54:18.000000000 -0500
@@ -245,6 +245,17 @@
                   sem_destroy(&sem);"
 . auto/feature
 
+if [ $ngx_found != yes ]; then
+
+    ngx_feature="POSIX semaphores in librt"
+    ngx_feature_libs="-lrt"
+    . auto/feature
+
+    if [ $ngx_found = yes ]; then
+        CORE_LIBS="$CORE_LIBS -lrt"
+    fi
+fi
+
 
 ngx_feature="struct msghdr.msg_control"
 ngx_feature_name="NGX_HAVE_MSGHDR_MSG_CONTROL"
diff -ru nginx-1.0.3/configure nginx-1.0.3-posix-sem-rt/configure
--- nginx-1.0.3/configure	2010-06-18 10:51:14.000000000 -0500
+++ nginx-1.0.3-posix-sem-rt/configure	2011-05-26 19:53:38.000000000 -0500
@@ -95,14 +95,14 @@
 have=NGX_HTTP_SCGI_TEMP_PATH value="\"$NGX_HTTP_SCGI_TEMP_PATH\""
 . auto/define
 
-. auto/make
-. auto/lib/make
-. auto/install
-
 if [ "$NGX_PLATFORM" != win32 ]; then
     . auto/unix
 fi
 
+. auto/make
+. auto/lib/make
+. auto/install
+
 # STUB
 . auto/stubs