diff --git a/include/amqpcpp/inbuffer.h b/include/amqpcpp/inbuffer.h
index c6bde4d5..38cda0e9 100644
--- a/include/amqpcpp/inbuffer.h
+++ b/include/amqpcpp/inbuffer.h
@@ -128,7 +128,7 @@ class InBuffer
      *  @param  size
      *  @return char*
      */
-    const char *nextData(uint32_t size);
+    const char *nextData(size_t size);
 
     /**
      *  The checker may access private data
diff --git a/src/inbuffer.cpp b/src/inbuffer.cpp
index 2f3208fe..e836a6c3 100644
--- a/src/inbuffer.cpp
+++ b/src/inbuffer.cpp
@@ -166,7 +166,7 @@ double InBuffer::nextDouble()
  *  @param  size
  *  @return char*
  */
-const char *InBuffer::nextData(uint32_t size)
+const char *InBuffer::nextData(size_t size)
 {
     // check if there is enough size
     BufferCheck check(this, size);