diff --git a/httpclient.php b/httpclient.php
index ba334ec..dc17d53 100644
--- a/httpclient.php
+++ b/httpclient.php
@@ -596,7 +596,10 @@ class Httpclient
     }
     if ($this->method !== "GET" && ! empty ($this->formData))
     {
-      $this->headersSent["Content-Type"] = "application/x-www-form-urlencoded";
+var_dump ($this->headersSent);
+      if (! key_exists ("Content-Type", $this->headersSent))
+        $this->headersSent["Content-Type"] =
+          "application/x-www-form-urlencoded";
       $len = 0;
       foreach ($this->formData as $key => $val)
       {