diff --git a/source/lib/sysdep/os/unix/udbg.cpp b/source/lib/sysdep/os/unix/udbg.cpp
index 9e7d33256b..415c28d803 100644
--- a/source/lib/sysdep/os/unix/udbg.cpp
+++ b/source/lib/sysdep/os/unix/udbg.cpp
@@ -105,7 +105,12 @@ void debug_puts(const wchar_t* text)
 
 void debug_puts(const wchar_t* text)
 {
-	printf("%ls", text); // must not use printf, since stdout is byte-oriented
+	// printf doesn't like %ls strings that contain non-ASCII characters
+	// (it tends to print nothing and return an error), so convert to
+	// UTF-8 before outputting
+	Status err;
+	std::string str = utf8_from_wstring(text, &err);
+	printf("%s", str.c_str());
 	fflush(stdout);
 }
 
diff --git a/source/scriptinterface/ScriptInterface.cpp b/source/scriptinterface/ScriptInterface.cpp
index 983b8b9284..bde484dd3b 100644
--- a/source/scriptinterface/ScriptInterface.cpp
+++ b/source/scriptinterface/ScriptInterface.cpp
@@ -316,10 +316,10 @@ JSBool print(JSContext* cx, uintN argc, jsval* vp)
 {
 	for (uintN i = 0; i < argc; ++i)
 	{
-		std::string str;
+		std::wstring str;
 		if (!ScriptInterface::FromJSVal(cx, JS_ARGV(cx, vp)[i], str))
 			return JS_FALSE;
-		debug_printf(L"%hs", str.c_str());
+		debug_printf(L"%ls", str.c_str());
 	}
 	fflush(stdout);
 	JS_SET_RVAL(cx, vp, JSVAL_VOID);