diff --git a/acme4j-client/src/main/java/org/shredzone/acme4j/AcmeClientFactory.java b/acme4j-client/src/main/java/org/shredzone/acme4j/AcmeClientFactory.java
index 1e8e969b..68f36d69 100644
--- a/acme4j-client/src/main/java/org/shredzone/acme4j/AcmeClientFactory.java
+++ b/acme4j-client/src/main/java/org/shredzone/acme4j/AcmeClientFactory.java
@@ -13,6 +13,8 @@
  */
 package org.shredzone.acme4j;
 
+import java.net.URI;
+import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.ServiceLoader;
@@ -45,6 +47,23 @@ public final class AcmeClientFactory {
      * @return {@link AcmeClient} for communication with the server
      */
     public static AcmeClient connect(String serverUri) throws AcmeException {
+        try {
+            return connect(new URI(serverUri));
+        } catch (URISyntaxException ex) {
+            throw new IllegalArgumentException(ex);
+        }
+    }
+
+    /**
+     * Connects to an ACME server and provides an {@link AcmeClient} for communication.
+     *
+     * @param serverUri
+     *            URI of the ACME server. This can either be a http/https URI to the
+     *            server's directory service, or a special acme URI for specific
+     *            implementations.
+     * @return {@link AcmeClient} for communication with the server
+     */
+    public static AcmeClient connect(URI serverUri) throws AcmeException {
         List<AcmeClientProvider> candidates = new ArrayList<>();
         for (AcmeClientProvider acp : ServiceLoader.load(AcmeClientProvider.class)) {
             if (acp.accepts(serverUri)) {
diff --git a/acme4j-client/src/main/java/org/shredzone/acme4j/provider/AcmeClientProvider.java b/acme4j-client/src/main/java/org/shredzone/acme4j/provider/AcmeClientProvider.java
index d02c6bd1..744399a7 100644
--- a/acme4j-client/src/main/java/org/shredzone/acme4j/provider/AcmeClientProvider.java
+++ b/acme4j-client/src/main/java/org/shredzone/acme4j/provider/AcmeClientProvider.java
@@ -41,7 +41,7 @@ public interface AcmeClientProvider {
      * @return {@code true} if this provider accepts the server URI, {@code false}
      *         otherwise
      */
-    boolean accepts(String serverUri);
+    boolean accepts(URI serverUri);
 
     /**
      * Connects to an {@link AcmeClient} for communication with the ACME server.
@@ -50,7 +50,7 @@ public interface AcmeClientProvider {
      *            Server URI to connect to
      * @return {@link AcmeClient} connected to the server
      */
-    AcmeClient connect(String serverUri);
+    AcmeClient connect(URI serverUri);
 
     /**
      * Creates a {@link Challenge} instance that is able to respond to the challenge of
diff --git a/acme4j-client/src/main/java/org/shredzone/acme4j/provider/GenericAcmeClientProvider.java b/acme4j-client/src/main/java/org/shredzone/acme4j/provider/GenericAcmeClientProvider.java
index f5dc08ae..5fea0872 100644
--- a/acme4j-client/src/main/java/org/shredzone/acme4j/provider/GenericAcmeClientProvider.java
+++ b/acme4j-client/src/main/java/org/shredzone/acme4j/provider/GenericAcmeClientProvider.java
@@ -14,7 +14,6 @@
 package org.shredzone.acme4j.provider;
 
 import java.net.URI;
-import java.net.URISyntaxException;
 
 import org.shredzone.acme4j.AcmeClient;
 import org.shredzone.acme4j.impl.GenericAcmeClient;
@@ -30,22 +29,18 @@ import org.shredzone.acme4j.impl.GenericAcmeClient;
 public class GenericAcmeClientProvider extends AbstractAcmeClientProvider {
 
     @Override
-    public boolean accepts(String serverUri) {
-        return serverUri.startsWith("http://") || serverUri.startsWith("https://");
+    public boolean accepts(URI serverUri) {
+        return "http".equals(serverUri.getScheme())
+                        || "https".equals(serverUri.getScheme());
     }
 
     @Override
-    public AcmeClient connect(String serverUri) {
+    public AcmeClient connect(URI serverUri) {
         if (!accepts(serverUri)) {
             throw new IllegalArgumentException("This provider does not accept " + serverUri);
         }
 
-        try {
-            URI directoryUri = new URI(serverUri);
-            return new GenericAcmeClient(this, directoryUri);
-        } catch (URISyntaxException ex) {
-            throw new IllegalArgumentException(serverUri, ex);
-        }
+        return new GenericAcmeClient(this, serverUri);
     }
 
 }
diff --git a/acme4j-letsencrypt/src/main/java/org/shredzone/acme4j/provider/LetsEncryptAcmeClientProvider.java b/acme4j-letsencrypt/src/main/java/org/shredzone/acme4j/provider/LetsEncryptAcmeClientProvider.java
index 1696b5a3..1830fda4 100644
--- a/acme4j-letsencrypt/src/main/java/org/shredzone/acme4j/provider/LetsEncryptAcmeClientProvider.java
+++ b/acme4j-letsencrypt/src/main/java/org/shredzone/acme4j/provider/LetsEncryptAcmeClientProvider.java
@@ -51,25 +51,25 @@ public class LetsEncryptAcmeClientProvider extends AbstractAcmeClientProvider {
     private SSLSocketFactory sslSocketFactory;
 
     @Override
-    public boolean accepts(String serverUri) {
-        return serverUri.startsWith("acme://letsencrypt.org");
+    public boolean accepts(URI serverUri) {
+        return "acme".equals(serverUri.getScheme())
+                && "letsencrypt.org".equals(serverUri.getHost());
     }
 
     @Override
-    public AcmeClient connect(String serverUri) {
+    public AcmeClient connect(URI serverUri) {
+        if (accepts(serverUri)) {
+            throw new IllegalArgumentException("Unknown URI " + serverUri);
+        }
+
+        String path = serverUri.getPath();
         String directoryUri;
-        switch (serverUri) {
-            case "acme://letsencrypt.org/staging":
-                directoryUri = STAGING_DIRECTORY_URI;
-                break;
-
-            case "acme://letsencrypt.org/v01":
-            case "acme://letsencrypt.org":
-                directoryUri = V01_DIRECTORY_URI;
-                break;
-
-            default:
-                throw new IllegalArgumentException("Unknown URI " + serverUri);
+        if (path == null || "v01".equals(path)) {
+            directoryUri = V01_DIRECTORY_URI;
+        } else if ("staging".equals(path)) {
+            directoryUri = STAGING_DIRECTORY_URI;
+        } else {
+            throw new IllegalArgumentException("Unknown URI " + serverUri);
         }
 
         try {