diff --git a/dlls/wininet/Makefile.in b/dlls/wininet/Makefile.in
index 7e8111f811d..5fbb66be50e 100644
--- a/dlls/wininet/Makefile.in
+++ b/dlls/wininet/Makefile.in
@@ -1,3 +1,4 @@
+EXTRADEFS = -D_WININET_INTERNAL_
 MODULE    = wininet.dll
 IMPORTLIB = wininet
 IMPORTS   = $(ZLIB_PE_LIBS) mpr shlwapi shell32 user32 ws2_32 advapi32
diff --git a/include/wininet.h b/include/wininet.h
index cef5da15de2..f1c4e312281 100644
--- a/include/wininet.h
+++ b/include/wininet.h
@@ -23,7 +23,14 @@
 extern "C" {
 #endif
 
-#define INTERNETAPI
+#ifndef INTERNETAPI
+#ifdef _WININET_INTERNAL_
+# define INTERNETAPI
+#else
+# define INTERNETAPI DECLSPEC_IMPORT
+#endif
+#endif
+
 #define BOOLAPI INTERNETAPI BOOL WINAPI
 
 typedef LPVOID HINTERNET;