diff --git a/include/wx/mac/carbon/uma.h b/include/wx/mac/carbon/uma.h
index a389c0d7b2..10ae90dd27 100644
--- a/include/wx/mac/carbon/uma.h
+++ b/include/wx/mac/carbon/uma.h
@@ -107,7 +107,7 @@ OSStatus UMADrawThemePlacard( const Rect *inRect , ThemeDrawState inState ) ;
 // Quartz 
 
 CGDataProviderRef UMACGDataProviderCreateWithCFData( CFDataRef data );
-CGDataConsumerRef UMACGDataConsumerCreateWithCFData( CFDataRef data );
+CGDataConsumerRef UMACGDataConsumerCreateWithCFData( CFMutableDataRef data );
 
 #endif // wxUSE_GUI