diff --git a/src/client.c b/src/client.c
index b7f8a73a..ceb83f74 100644
--- a/src/client.c
+++ b/src/client.c
@@ -63,6 +63,10 @@ void client_destroy(client_t *client)
     while ((refbuf = refbuf_queue_remove(&client->queue)))
         refbuf_release(refbuf);
 
+    /* we need to free client specific format data (if any) */
+    if (client->free_client_data)
+        client->free_client_data (client);
+
     free(client->username);
 
     free(client);
diff --git a/src/client.h b/src/client.h
index 7f0e9c8e..d38d9677 100644
--- a/src/client.h
+++ b/src/client.h
@@ -42,6 +42,9 @@ typedef struct _client_tag
 
     /* Format-handler-specific data for this client */
     void *format_data;
+
+    /* function to call to release format specific resources */
+    void (*free_client_data)(struct _client_tag *client);
 } client_t;
 
 client_t *client_create(connection_t *con, http_parser_t *parser);
diff --git a/src/format_mp3.c b/src/format_mp3.c
index affa8ad3..4231d58b 100644
--- a/src/format_mp3.c
+++ b/src/format_mp3.c
@@ -59,6 +59,7 @@ static int format_mp3_get_buffer(format_plugin_t *self, char *data,
 static refbuf_queue_t *format_mp3_get_predata(format_plugin_t *self);
 static void *format_mp3_create_client_data(format_plugin_t *self,
         source_t *source, client_t *client);
+static void free_mp3_client_data (client_t *client);
 static int format_mp3_write_buf_to_client(format_plugin_t *self,
         client_t *client, unsigned char *buf, int len);
 static void format_mp3_send_headers(format_plugin_t *self, 
@@ -394,6 +395,7 @@ static void *format_mp3_create_client_data(format_plugin_t *self,
 
     data->interval = ICY_METADATA_INTERVAL;
     data->offset = 0;
+    client->free_client_data = free_mp3_client_data;
 
     metadata = httpp_getvar(client->parser, "icy-metadata");
     if(metadata)
@@ -402,6 +404,14 @@ static void *format_mp3_create_client_data(format_plugin_t *self,
     return data;
 }
 
+
+static void free_mp3_client_data (client_t *client)
+{
+    free (client->format_data);
+    client->format_data = NULL;
+}
+
+
 static void format_mp3_send_headers(format_plugin_t *self,
         source_t *source, client_t *client)
 {