diff --git a/org.eclipse.jgit.http.test/META-INF/MANIFEST.MF b/org.eclipse.jgit.http.test/META-INF/MANIFEST.MF
index 44ce9c4..0bcc57c 100644
--- a/org.eclipse.jgit.http.test/META-INF/MANIFEST.MF
+++ b/org.eclipse.jgit.http.test/META-INF/MANIFEST.MF
@@ -28,6 +28,7 @@
  org.eclipse.jetty.util.log;version="[9.4.5,10.0.0)",
  org.eclipse.jetty.util.security;version="[9.4.5,10.0.0)",
  org.eclipse.jetty.util.thread;version="[9.4.5,10.0.0)",
+ org.eclipse.jgit.api;version="[5.11.0,5.12.0)",
  org.eclipse.jgit.errors;version="[5.11.0,5.12.0)",
  org.eclipse.jgit.http.server;version="[5.11.0,5.12.0)",
  org.eclipse.jgit.http.server.glue;version="[5.11.0,5.12.0)",
diff --git a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/SmartClientSmartServerTest.java b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/SmartClientSmartServerTest.java
index def52ff..89a2541 100644
--- a/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/SmartClientSmartServerTest.java
+++ b/org.eclipse.jgit.http.test/tst/org/eclipse/jgit/http/test/SmartClientSmartServerTest.java
@@ -23,12 +23,15 @@
 import static org.junit.Assert.fail;
 
 import java.io.ByteArrayOutputStream;
+import java.io.File;
 import java.io.IOException;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.io.Writer;
+import java.net.Proxy;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.net.URL;
 import java.nio.charset.StandardCharsets;
 import java.text.MessageFormat;
 import java.util.Collections;
@@ -52,6 +55,8 @@
 import org.eclipse.jetty.servlet.FilterHolder;
 import org.eclipse.jetty.servlet.ServletContextHandler;
 import org.eclipse.jetty.servlet.ServletHolder;
+import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.api.TransportConfigCallback;
 import org.eclipse.jgit.errors.RemoteRepositoryException;
 import org.eclipse.jgit.errors.TransportException;
 import org.eclipse.jgit.errors.UnsupportedCredentialItem;
@@ -91,6 +96,8 @@
 import org.eclipse.jgit.transport.URIish;
 import org.eclipse.jgit.transport.UploadPack;
 import org.eclipse.jgit.transport.UsernamePasswordCredentialsProvider;
+import org.eclipse.jgit.transport.http.HttpConnection;
+import org.eclipse.jgit.transport.http.HttpConnectionFactory;
 import org.eclipse.jgit.util.HttpSupport;
 import org.eclipse.jgit.util.SystemReader;
 import org.junit.Before;
@@ -638,6 +645,63 @@
 				.getResponseHeader(HDR_CONTENT_TYPE));
 	}
 
+	@Test
+	public void test_CloneWithCustomFactory() throws Exception {
+		HttpConnectionFactory globalFactory = HttpTransport
+				.getConnectionFactory();
+		HttpConnectionFactory failingConnectionFactory = new HttpConnectionFactory() {
+
+			@Override
+			public HttpConnection create(URL url) throws IOException {
+				throw new IOException("Should not be reached");
+			}
+
+			@Override
+			public HttpConnection create(URL url, Proxy proxy)
+					throws IOException {
+				throw new IOException("Should not be reached");
+			}
+		};
+		HttpTransport.setConnectionFactory(failingConnectionFactory);
+		try {
+			File tmp = createTempDirectory("cloneViaApi");
+			boolean[] localFactoryUsed = { false };
+			TransportConfigCallback callback = new TransportConfigCallback() {
+
+				@Override
+				public void configure(Transport transport) {
+					if (transport instanceof TransportHttp) {
+						((TransportHttp) transport).setHttpConnectionFactory(
+								new HttpConnectionFactory() {
+
+									@Override
+									public HttpConnection create(URL url)
+											throws IOException {
+										localFactoryUsed[0] = true;
+										return globalFactory.create(url);
+									}
+
+									@Override
+									public HttpConnection create(URL url,
+											Proxy proxy) throws IOException {
+										localFactoryUsed[0] = true;
+										return globalFactory.create(url, proxy);
+									}
+								});
+					}
+				}
+			};
+			try (Git git = Git.cloneRepository().setDirectory(tmp)
+					.setTransportConfigCallback(callback)
+					.setURI(remoteURI.toPrivateString()).call()) {
+				assertTrue("Should have used the local HttpConnectionFactory",
+						localFactoryUsed[0]);
+			}
+		} finally {
+			HttpTransport.setConnectionFactory(globalFactory);
+		}
+	}
+
 	private void initialClone_Redirect(int nofRedirects, int code)
 			throws Exception {
 		initialClone_Redirect(nofRedirects, code, false);
diff --git a/org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties b/org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties
index bfb29a8..e40d0f0 100644
--- a/org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties
+++ b/org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties
@@ -311,6 +311,7 @@
 hoursAgo={0} hours ago
 httpConfigCannotNormalizeURL=Cannot normalize URL path {0}: too many .. segments
 httpConfigInvalidURL=Cannot parse URL from subsection http.{0} in git config; ignored.
+httpFactoryInUse=Changing the HTTP connection factory after an HTTP connection has already been opened is not allowed.
 hugeIndexesAreNotSupportedByJgitYet=Huge indexes are not supported by jgit, yet
 hunkBelongsToAnotherFile=Hunk belongs to another file
 hunkDisconnectedFromFile=Hunk disconnected from file
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
index 09ec529..5e31eae 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
@@ -339,6 +339,7 @@
 	/***/ public String hoursAgo;
 	/***/ public String httpConfigCannotNormalizeURL;
 	/***/ public String httpConfigInvalidURL;
+	/***/ public String httpFactoryInUse;
 	/***/ public String hugeIndexesAreNotSupportedByJgitYet;
 	/***/ public String hunkBelongsToAnotherFile;
 	/***/ public String hunkDisconnectedFromFile;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/HttpTransport.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/HttpTransport.java
index 49c8b58..febeb3c 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/HttpTransport.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/HttpTransport.java
@@ -26,7 +26,7 @@
 	 *
 	 * @since 3.3
 	 */
-	protected static HttpConnectionFactory connectionFactory = new JDKHttpConnectionFactory();
+	protected static volatile HttpConnectionFactory connectionFactory = new JDKHttpConnectionFactory();
 
 	/**
 	 * Get the {@link org.eclipse.jgit.transport.http.HttpConnectionFactory}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
index 9d40f02..4367f99 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java
@@ -75,6 +75,7 @@
 
 import javax.net.ssl.SSLHandshakeException;
 
+import org.eclipse.jgit.annotations.NonNull;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.NoRemoteRepositoryException;
 import org.eclipse.jgit.errors.NotSupportedException;
@@ -95,6 +96,7 @@
 import org.eclipse.jgit.transport.HttpAuthMethod.Type;
 import org.eclipse.jgit.transport.HttpConfig.HttpRedirectMode;
 import org.eclipse.jgit.transport.http.HttpConnection;
+import org.eclipse.jgit.transport.http.HttpConnectionFactory;
 import org.eclipse.jgit.util.HttpSupport;
 import org.eclipse.jgit.util.IO;
 import org.eclipse.jgit.util.RawParseUtils;
@@ -260,6 +262,10 @@
 
 	private boolean sslFailure = false;
 
+	private HttpConnectionFactory factory;
+
+	private boolean factoryUsed;
+
 	/**
 	 * All stored cookies bound to this repo (independent of the baseUrl)
 	 */
@@ -282,6 +288,7 @@
 		sslVerify = http.isSslVerify();
 		cookieFile = getCookieFileFromConfig(http);
 		relevantCookies = filterCookies(cookieFile, baseUrl);
+		factory = HttpTransport.getConnectionFactory();
 	}
 
 	private URL toURL(URIish urish) throws MalformedURLException {
@@ -324,6 +331,7 @@
 		sslVerify = http.isSslVerify();
 		cookieFile = getCookieFileFromConfig(http);
 		relevantCookies = filterCookies(cookieFile, baseUrl);
+		factory = HttpTransport.getConnectionFactory();
 	}
 
 	/**
@@ -360,6 +368,42 @@
 		return (FetchConnection) f;
 	}
 
+	/**
+	 * Sets the {@link HttpConnectionFactory} to be used by this
+	 * {@link TransportHttp} instance.
+	 * <p>
+	 * If no factory is set explicitly, the {@link TransportHttp} instance uses
+	 * the {@link HttpTransport#getConnectionFactory() globally defined
+	 * factory}.
+	 * </p>
+	 *
+	 * @param customFactory
+	 *            the {@link HttpConnectionFactory} to use
+	 * @throws IllegalStateException
+	 *             if an HTTP/HTTPS connection has already been opened on this
+	 *             {@link TransportHttp} instance
+	 * @since 5.11
+	 */
+	public void setHttpConnectionFactory(
+			@NonNull HttpConnectionFactory customFactory) {
+		if (factoryUsed) {
+			throw new IllegalStateException(JGitText.get().httpFactoryInUse);
+		}
+		factory = customFactory;
+	}
+
+	/**
+	 * Retrieves the {@link HttpConnectionFactory} used by this
+	 * {@link TransportHttp} instance.
+	 *
+	 * @return the {@link HttpConnectionFactory}
+	 * @since 5.11
+	 */
+	@NonNull
+	public HttpConnectionFactory getHttpConnectionFactory() {
+		return factory;
+	}
+
 	/** {@inheritDoc} */
 	@Override
 	public FetchConnection openFetch() throws TransportException,
@@ -916,7 +960,8 @@
 		}
 
 		final Proxy proxy = HttpSupport.proxyFor(proxySelector, u);
-		HttpConnection conn = connectionFactory.create(u, proxy);
+		factoryUsed = true;
+		HttpConnection conn = factory.create(u, proxy);
 
 		if (!sslVerify && "https".equals(u.getProtocol())) { //$NON-NLS-1$
 			HttpSupport.disableSslVerify(conn);