diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java
index 6e417b33b..1d8c0d01b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java
@@ -1024,7 +1024,7 @@ public class DirCacheCheckout {
 	private static boolean isValidPathSegment(CanonicalTreeParser t) {
 		String osName = SystemReader.getInstance().getProperty("os.name");
 		boolean isWindows = "Windows".equals(osName);
-		boolean isOSX = "Darwin".equals(osName) || "Mac OS X".equals(osName);
+		boolean isOSX = SystemReader.getInstance().isMacOS();
 		boolean ignCase = isOSX || isWindows;
 
 		int ptr = t.getNameOffset();
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 36d3b9484..742afe135 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
@@ -44,8 +44,6 @@ package org.eclipse.jgit.util;
 
 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;
@@ -58,7 +56,7 @@ abstract class FS_POSIX extends FS {
 		if (gitExe != null)
 			return gitExe.getParentFile().getParentFile();
 
-		if (isMacOS()) {
+		if (SystemReader.getInstance().isMacOS()) {
 			// On MacOSX, PATH is shorter when Eclipse is launched from the
 			// Finder than from a terminal. Therefore try to launch bash as a
 			// login shell and search using that.
@@ -87,10 +85,7 @@ abstract class FS_POSIX extends FS {
 
 	@Override
 	public boolean isCaseSensitive() {
-		if (isMacOS())
-			return false;
-		else
-			return true;
+		return !SystemReader.getInstance().isMacOS();
 	}
 
 	@Override
@@ -105,14 +100,4 @@ abstract class FS_POSIX extends FS {
 		proc.command(argv);
 		return proc;
 	}
-
-	private static boolean isMacOS() {
-		final String osDotName = AccessController
-				.doPrivileged(new PrivilegedAction<String>() {
-					public String run() {
-						return System.getProperty("os.name");
-					}
-				});
-		return "Mac OS X".equals(osDotName) || "Darwin".equals(osDotName);
-	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java
index 4181a2fb2..4298fbcf7 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java
@@ -49,6 +49,8 @@ package org.eclipse.jgit.util;
 import java.io.File;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Locale;
@@ -237,4 +239,17 @@ public abstract class SystemReader {
 		return DateFormat.getDateTimeInstance(dateStyle, timeStyle);
 	}
 
+	/**
+	 * @return true if we are running on Mac OS X
+	 */
+	public boolean isMacOS() {
+		String osDotName = AccessController
+				.doPrivileged(new PrivilegedAction<String>() {
+					public String run() {
+						return getProperty("os.name");
+					}
+				});
+		return "Mac OS X".equals(osDotName) || "Darwin".equals(osDotName);
+	}
+
 }