diff -Nru mongodb-src-r2.0.2.orig/db/cmdline.cpp mongodb-src-r2.0.2/db/cmdline.cpp
--- mongodb-src-r2.0.2.orig/db/cmdline.cpp	2011-12-14 12:18:48.000000000 -0500
+++ mongodb-src-r2.0.2/db/cmdline.cpp	2012-01-15 01:15:01.985803346 -0500
@@ -263,11 +263,34 @@
             cout.flush();
             cerr.flush();
 
+            int pipes[2];
+            if (pipe(pipes) < 0) {
+                cout << "Can't create pipe while forking server process: " << strerror(errno) << endl;
+                ::exit(-1);
+            }
+
             pid_t c = fork();
             if ( c ) {
+                char buf[1];
+                // parent; here, we close out the write side of the pipe and
+                // block on a single byte read from the final child to tell us
+                // when it is done
+                close(pipes[1]);
+                ssize_t bytes = read(pipes[0], buf, 1);
+                close(pipes[0]);
+                if (bytes != 1) {
+                    // in this case, the child failed to start for some reason.
+                    // we assume that the child wrote the error information, so
+                    // all we have to do is exit with an error code
+                    ::exit(-1);
+                }
+
                 _exit(0);
             }
 
+            // in the child, close out the read end of the pipe
+            close(pipes[0]);
+
             if ( chdir("/") < 0 ) {
                 cout << "Cant chdir() while forking server process: " << strerror(errno) << endl;
                 ::exit(-1);
@@ -301,6 +324,21 @@
 
             setupCoreSignals();
             setupSignals( true );
+
+            if ( params.count("pidfilepath")) {
+                writePidFile( params["pidfilepath"].as<string>() );
+            }
+
+            ssize_t bytes = write(pipes[1], "a", 1);
+            close(pipes[1]);
+            if (bytes < 0) {
+                cout << "Can't write to the parent pipe: " << strerror(errno) << endl;
+                ::exit(-1);
+            }
+            else if (bytes != 1) {
+                cout << "Can't write to the parent pipe: unknown error" << endl;
+                ::exit(-1);
+            }
         }
 
 #endif
@@ -311,7 +349,9 @@
             initLogging( logpath , params.count( "logappend" ) );
         }
 
-        if ( params.count("pidfilepath")) {
+        // if this was a forking configuration, the pidfile was written above;
+        // if not, we have to write it here
+        if ( !params.count("fork") && params.count("pidfilepath")) {
             writePidFile( params["pidfilepath"].as<string>() );
         }