diff --git a/composer.json b/composer.json
index 3a7e00ba..32deb3f2 100755
--- a/composer.json
+++ b/composer.json
@@ -6,7 +6,7 @@
   "description" : "HTTP protocol support for the XP Framework",
   "keywords": ["module", "xp"],
   "require" : {
-    "xp-framework/core": "^12.0 | ^11.0 | ^10.0",
+    "xp-framework/core": "^12.11 | ^11.11",
     "xp-framework/logging": "^11.0 | ^10.0",
     "xp-framework/networking": "^11.0 | ^10.0 | ^9.3",
     "php" : ">=7.4.0"
diff --git a/src/main/php/peer/http/CurlHttpTransport.class.php b/src/main/php/peer/http/CurlHttpTransport.class.php
index 45cf3531..94342ccd 100755
--- a/src/main/php/peer/http/CurlHttpTransport.class.php
+++ b/src/main/php/peer/http/CurlHttpTransport.class.php
@@ -1,6 +1,6 @@
 <?php namespace peer\http;
 
-use io\IOException;
+use io\OperationFailed;
 use io\streams\MemoryInputStream;
 use peer\URL;
 
@@ -32,7 +32,7 @@ public function __construct(URL $url, $arg) {
    * @param   float $connectTimeout default 2.0
    * @param   float $readTimeout default 60.0
    * @return  peer.http.HttpOutputStream
-   * @throws  io.IOException
+   * @throws  io.OperationFailed
    */
   public function open(HttpRequest $request, $connectTimeout= 2.0, $readTimeout= 60.0) {
     static $versions= [
@@ -85,7 +85,7 @@ public function open(HttpRequest $request, $connectTimeout= 2.0, $readTimeout= 6
    *
    * @param  peer.http.HttpOutputStream $stream
    * @return peer.http.HttpResponse
-   * @throws  io.IOException
+   * @throws  io.OperationFailed
    */
   public function finish($stream) {
     $stream->close();
@@ -98,7 +98,7 @@ public function finish($stream) {
       $error= curl_errno($stream->handle);
       $message= curl_error($stream->handle);
       curl_close($stream->handle);
-      throw new IOException($error.' '.$message);
+      throw new OperationFailed($error.' '.$message);
     }
 
     // Strip "HTTP/x.x 200 Connection established" which is followed by
@@ -120,7 +120,7 @@ public function finish($stream) {
    * @param   int $timeout default 60
    * @param   float $connecttimeout default 2.0
    * @return  peer.http.HttpResponse response object
-   * @throws  io.IOException
+   * @throws  io.OperationFailed
    */
   public function send(HttpRequest $request, $timeout= 60, $connecttimeout= 2.0) {
     static $versions= [
@@ -176,7 +176,7 @@ public function send(HttpRequest $request, $timeout= 60, $connecttimeout= 2.0) {
       $errno= curl_errno($handle);
       $error= curl_error($handle);
       curl_close($handle);
-      throw new \io\IOException(sprintf('%d: %s', $errno, $error));
+      throw new \io\OperationFailed(sprintf('%d: %s', $errno, $error));
     }
     // ensure handle is closed
     curl_close($handle);
diff --git a/src/main/php/peer/http/HttpConnection.class.php b/src/main/php/peer/http/HttpConnection.class.php
index 7d5fed59..82dd08f4 100755
--- a/src/main/php/peer/http/HttpConnection.class.php
+++ b/src/main/php/peer/http/HttpConnection.class.php
@@ -177,7 +177,7 @@ public function create(HttpRequest $r) {
    * @param   var $parameters
    * @param   [:string] $headers default array()
    * @return  peer.http.HttpResponse response object
-   * @throws  io.IOException
+   * @throws  io.OperationFailed
    */
   public function request($method, $parameters= null, $headers= []) {
     $r= new HttpRequest($this->url);
diff --git a/src/main/php/peer/http/HttpResponse.class.php b/src/main/php/peer/http/HttpResponse.class.php
index 1ee04118..edf52b6f 100755
--- a/src/main/php/peer/http/HttpResponse.class.php
+++ b/src/main/php/peer/http/HttpResponse.class.php
@@ -148,7 +148,7 @@ public function readData($size= 8192) {
     if (!($indicator= $this->scanUntil("\n"))) return $this->closeStream();
     if (!(sscanf($indicator, "%x%s\r", $chunksize, $extension))) {
       $this->closeStream();
-      throw new \io\IOException(sprintf(
+      throw new \io\OperationFailed(sprintf(
         'Chunked transfer encoding: Indicator line "%s" invalid', 
         addcslashes($indicator, "\0..\17")
       ));
diff --git a/src/main/php/peer/http/SSLSocketHttpTransport.class.php b/src/main/php/peer/http/SSLSocketHttpTransport.class.php
index c879790f..9a053831 100755
--- a/src/main/php/peer/http/SSLSocketHttpTransport.class.php
+++ b/src/main/php/peer/http/SSLSocketHttpTransport.class.php
@@ -1,6 +1,6 @@
 <?php namespace peer\http;
 
-use io\IOException;
+use io\OperationFailed;
 use peer\{CryptoSocket, URL};
 use util\Objects;
 
@@ -56,7 +56,7 @@ protected function newSocket(URL $url, $arg) {
    * @param  peer.http.HttpRequest $request
    * @param  peer.URL $url
    * @return void
-   * @throws io.IOException
+   * @throws io.OperationFailed
    */
   protected function proxy($s, $request, $url) {
     $connect= sprintf(
@@ -70,14 +70,14 @@ protected function proxy($s, $request, $url) {
     // Verify we are actually talking to a HTTP proxy
     $handshake= $s->read();
     if (4 !== ($r= sscanf($handshake, "HTTP/%*d.%*d %d %[^\r]", $status, $message))) {
-      throw new IOException('Proxy did not answer with valid HTTP: '.$handshake);
+      throw new OperationFailed('Proxy did not answer with valid HTTP: '.$handshake);
     }
 
     // Verify proxy answers with a 200 status code
     while ($line= $s->readLine()) $handshake.= $line."\n";
     $this->cat && $this->cat->info('<<<', $handshake);
     if (200 !== $status) {
-      throw new IOException('Cannot connect through proxy: #'.$status.' '.$message);
+      throw new OperationFailed('Cannot connect through proxy: #'.$status.' '.$message);
     }
 
     // Enable cryptography
@@ -87,7 +87,7 @@ protected function proxy($s, $request, $url) {
       foreach (self::$crypto as $name => $flag) {
         if ($flag === $this->socket->cryptoImpl & $flag) $methods.= ', '.$name;
       }
-      throw new IOException('Cannot establish secure connection, tried '.substr($methods, 2));
+      throw new OperationFailed('Cannot establish secure connection, tried '.substr($methods, 2));
     }
 
     $this->cat && $this->cat->debug('@@@ Enabled cryptography: '.Objects::stringOf(stream_get_meta_data($s->getHandle())['crypto']));