diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportLocal.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportLocal.java
index c9b18be1f..3ede748b3 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportLocal.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportLocal.java
@@ -55,6 +55,7 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.PipedInputStream;
 import java.io.PipedOutputStream;
+import java.util.Map;
 
 import org.eclipse.jgit.JGitText;
 import org.eclipse.jgit.errors.NotSupportedException;
@@ -146,22 +147,22 @@ class TransportLocal extends Transport implements PackTransport {
 	protected Process spawn(final String cmd)
 			throws TransportException {
 		try {
-			final String[] args;
-
-			if (cmd.startsWith("git-")) {
-				args = new String[] { "git", cmd.substring(4), PWD };
-			} else {
-				final int gitspace = cmd.indexOf("git ");
-				if (gitspace >= 0) {
-					final String git = cmd.substring(0, gitspace + 3);
-					final String subcmd = cmd.substring(gitspace + 4);
-					args = new String[] { git, subcmd, PWD };
-				} else {
-					args = new String[] { cmd, PWD };
-				}
-			}
-
-			return Runtime.getRuntime().exec(args, null, remoteGitDir);
+			String[] args = { "." };
+			ProcessBuilder proc = local.getFS().runInShell(cmd, args);
+			proc.directory(remoteGitDir);
+
+			// Remove the same variables CGit does.
+			Map<String, String> env = proc.environment();
+			env.remove("GIT_ALTERNATE_OBJECT_DIRECTORIES");
+			env.remove("GIT_CONFIG");
+			env.remove("GIT_CONFIG_PARAMETERS");
+			env.remove("GIT_DIR");
+			env.remove("GIT_WORK_TREE");
+			env.remove("GIT_GRAFT_FILE");
+			env.remove("GIT_INDEX_FILE");
+			env.remove("GIT_NO_REPLACE_OBJECTS");
+
+			return proc.start();
 		} catch (IOException err) {
 			throw new TransportException(uri, err.getMessage(), err);
 		}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java
index 87d5395bf..8faefede1 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java
@@ -255,4 +255,18 @@ public abstract class FS {
 
 	/** @return the $prefix directory C Git would use. */
 	public abstract File gitPrefix();
+
+	/**
+	 * Initialize a ProcesssBuilder to run a command using the system shell.
+	 *
+	 * @param cmd
+	 *            command to execute. This string should originate from the
+	 *            end-user, and thus is platform specific.
+	 * @param args
+	 *            arguments to pass to command. These should be protected from
+	 *            shell evaluation.
+	 * @return a partially completed process builder. Caller should finish
+	 *         populating directory, environment, and then start the process.
+	 */
+	public abstract ProcessBuilder runInShell(String cmd, String[] args);
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_POSIX.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_POSIX.java
index 0ebf2e307..e69596313 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_POSIX.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_POSIX.java
@@ -46,6 +46,9 @@ import java.io.File;
 import java.nio.charset.Charset;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 
 abstract class FS_POSIX extends FS {
 	@Override
@@ -69,6 +72,19 @@ abstract class FS_POSIX extends FS {
 		return null;
 	}
 
+	@Override
+	public ProcessBuilder runInShell(String cmd, String[] args) {
+		List<String> argv = new ArrayList<String>(4 + args.length);
+		argv.add("sh");
+		argv.add("-c");
+		argv.add(cmd + " \"$@\"");
+		argv.add(cmd);
+		argv.addAll(Arrays.asList(args));
+		ProcessBuilder proc = new ProcessBuilder();
+		proc.command(argv);
+		return proc;
+	}
+
 	private static boolean isMacOS() {
 		final String osDotName = AccessController
 				.doPrivileged(new PrivilegedAction<String>() {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32.java
index 0ee7a6bc5..0e05de091 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32.java
@@ -48,6 +48,9 @@ import java.io.File;
 import java.nio.charset.Charset;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 
 class FS_Win32 extends FS {
 	static boolean detect() {
@@ -114,4 +117,16 @@ class FS_Win32 extends FS {
 
 		return super.userHomeImpl();
 	}
+
+	@Override
+	public ProcessBuilder runInShell(String cmd, String[] args) {
+		List<String> argv = new ArrayList<String>(3 + args.length);
+		argv.add("cmd.exe");
+		argv.add("/c");
+		argv.add(cmd);
+		argv.addAll(Arrays.asList(args));
+		ProcessBuilder proc = new ProcessBuilder();
+		proc.command(argv);
+		return proc;
+	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32_Cygwin.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32_Cygwin.java
index 15da505f5..4e8841c99 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32_Cygwin.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS_Win32_Cygwin.java
@@ -46,6 +46,9 @@ package org.eclipse.jgit.util;
 import java.io.File;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 
 class FS_Win32_Cygwin extends FS_Win32 {
 	private static String cygpath;
@@ -86,4 +89,17 @@ class FS_Win32_Cygwin extends FS_Win32 {
 			return super.userHomeImpl();
 		return resolve(new File("."), home);
 	}
+
+	@Override
+	public ProcessBuilder runInShell(String cmd, String[] args) {
+		List<String> argv = new ArrayList<String>(4 + args.length);
+		argv.add("sh.exe");
+		argv.add("-c");
+		argv.add(cmd + " \"$@\"");
+		argv.add(cmd);
+		argv.addAll(Arrays.asList(args));
+		ProcessBuilder proc = new ProcessBuilder();
+		proc.command(argv);
+		return proc;
+	}
 }