diff --git a/ndn-cpp/key.cpp b/ndn-cpp/key.cpp
index b453471..ef57265 100644
--- a/ndn-cpp/key.cpp
+++ b/ndn-cpp/key.cpp
@@ -18,7 +18,7 @@
   
   keyLocatorStruct.keyDataLength = keyData_.size();
   if (keyData_.size() > 0)
-    keyLocatorStruct.keyData = (unsigned char *)keyData_.buf();
+    keyLocatorStruct.keyData = (uint8_t *)keyData_.buf();
   else
     keyLocatorStruct.keyData = 0;