diff --git a/chrome/content/zotero/xpcom/standalone.js b/chrome/content/zotero/xpcom/standalone.js
index c89db58a1b..bd380f788c 100644
--- a/chrome/content/zotero/xpcom/standalone.js
+++ b/chrome/content/zotero/xpcom/standalone.js
@@ -57,7 +57,7 @@ Zotero.Standalone = new function () {
 				var nBytes = data.length;
 				var inputStream = Cc["@mozilla.org/io/string-input-stream;1"].
 					createInstance(Ci.nsIStringInputStream);
-				inputStream.setData(data, nBytes);
+				inputStream.setByteStringData(data);
 				this.oldListener.onDataAvailable(aRequest, aContext, inputStream, 0, nBytes);
 			}
 			this.oldListener.onStopRequest(aRequest, aContext, aStatusCode);
diff --git a/chrome/content/zotero/xpcom/utilities_internal.js b/chrome/content/zotero/xpcom/utilities_internal.js
index 339474ca70..46899fad5d 100644
--- a/chrome/content/zotero/xpcom/utilities_internal.js
+++ b/chrome/content/zotero/xpcom/utilities_internal.js
@@ -284,7 +284,7 @@ Zotero.Utilities.Internal = {
 		
 		var is = Components.classes["@mozilla.org/io/string-input-stream;1"]
 			.createInstance(Ci.nsIStringInputStream);
-		is.setData(data, data.length);
+		is.setByteStringData(data);
 		
 		var bis = Components.classes["@mozilla.org/binaryinputstream;1"]
 			.createInstance(Components.interfaces.nsIBinaryInputStream);