diff --git a/dlls/glu32/glu.c b/dlls/glu32/glu.c
index bdcb6202f29..ee4986eaba3 100644
--- a/dlls/glu32/glu.c
+++ b/dlls/glu32/glu.c
@@ -270,6 +270,24 @@ const GLubyte * WINAPI wine_gluErrorString( GLenum errCode )
     return NULL;
 }
 
+/***********************************************************************
+ *		gluErrorUnicodeStringEXT (GLU32.@)
+ */
+const WCHAR * WINAPI wine_gluErrorUnicodeStringEXT( GLenum errCode )
+{
+    static WCHAR errorsW[NB_ERRORS][64];
+    unsigned int i, j;
+
+    for (i = 0; i < NB_ERRORS; i++)
+    {
+        if (errors[i].err != errCode) continue;
+        if (!errorsW[i][0])  /* errors use only ASCII, do a simple mapping */
+            for (j = 0; errors[i].str[j]; j++) errorsW[i][j] = (WCHAR)errors[i].str[j];
+        return errorsW[i];
+    }
+    return NULL;
+}
+
 /***********************************************************************
  *		gluScaleImage (GLU32.@)
  */
diff --git a/dlls/glu32/glu32.spec b/dlls/glu32/glu32.spec
index 8f98fecbfb7..5b416fde78d 100644
--- a/dlls/glu32/glu32.spec
+++ b/dlls/glu32/glu32.spec
@@ -15,7 +15,7 @@
 @ stdcall gluEndSurface(ptr) wine_gluEndSurface
 @ stdcall gluEndTrim(ptr) wine_gluEndTrim
 @ stdcall gluErrorString(long) wine_gluErrorString
-@ stub gluErrorUnicodeStringEXT
+@ stdcall gluErrorUnicodeStringEXT(long) wine_gluErrorUnicodeStringEXT
 @ stdcall gluGetNurbsProperty(ptr long ptr) wine_gluGetNurbsProperty
 @ stdcall gluGetString(long) wine_gluGetString
 @ stdcall gluGetTessProperty(ptr long ptr) wine_gluGetTessProperty