diff --git a/otk/ustring.cc b/otk/ustring.cc
index b6432d44..7ac89bf7 100644
--- a/otk/ustring.cc
+++ b/otk/ustring.cc
@@ -132,13 +132,13 @@ ustring& ustring::operator=(const ustring& other)
   return *this;
 }
 
-ustring::ustring(const std::string& src)
-  : _string(src), _utf8(true)
+ustring::ustring(const std::string& src, bool utf8)
+  : _string(src), _utf8(utf8)
 {
 }
 
-ustring::ustring(const char* src)
-  : _string(src), _utf8(true)
+ustring::ustring(const char* src, bool utf8)
+  : _string(src), _utf8(utf8)
 {
 }
 
diff --git a/otk/ustring.hh b/otk/ustring.hh
index be2a59c8..8ee066d3 100644
--- a/otk/ustring.hh
+++ b/otk/ustring.hh
@@ -124,8 +124,8 @@ public:
   
   ustring(const ustring& other);
   ustring& operator=(const ustring& other);
-  ustring(const std::string& src);
-  ustring(const char* src);
+  ustring(const std::string& src, bool utf8 = true);
+  ustring(const char* src, bool utf8 = true);
 
   // append to the string